December Birthstone: What You Need to Know About Tanzanite, Turquoise and Zircon

November 29, 2017

If you had to pick one December birthstone, which would it be: tanzanite, turquoise or zircon? From the blue to bluish purple of tanzanite, to the intense blue and green of turquoise, to the rainbow varieties of zircon, there’s a color for you. We help you pick one.

In this blog, we cover:

Tanzanite: The Newest December Birthstone
Gemological properties of tanzanite
Tanzanite history & lore
Where tanzanite comes from
Qualities to look for in tanzanite
Tanzanite treatments, care & cleaning

Turquoise: The Historic December Birthstone
Gemological properties of turquoise
Turquoise history and lore
Where turquoise comes from
Qualities to look for in turquoise
Turquoise treatments, care & cleaning

Zircon: The Colorful December Birthstone
Gemological properties of zircon
Zircon history & lore
Where zircon comes from
Qualities to look for in zircon
Zircon treatments, care & cleaning

TANZANITE: THE NEWEST DECEMBER BIRTHSTONE

A trilliant cut tanzanite with an exceptional violetish blue color captivates as the December birthstone. Photo: Robert Weldon/GIA

Gemological properties of tanzanite

Tanzanite is the blue to violet to bluish purple variety of the mineral zoisite. This December birthstone is mined commercially in only one area of the world — the Merelani Hills of Tanzania — from where it gets its name.

Tanzanite’s appearance is influenced greatly by its pleochroism – the different colors some gemstones show when viewed from different directions. Tanzanite can be violetish blue or deep blue – similar to a sapphire color – or much more purplish. Often, both the violetish blue and purple are readily visible in a fashioned stone when it is gently rocked and tilted. This December birthstone is rather fragile, ranking 6 to 7 on the Mohs scale of hardness; a diamond is a 10. The scale is exponential, meaning that a diamond is many times harder than tanzanite. Tanzanite’s toughness (the ability of a gem material to resist breaking, chipping or cracking) is fair to poor because it has one direction of cleavage (the tendency of a crystalline mineral to break along atomic planes) and is sensitive to sudden temperature changes.

Gemologists love tanzanite because it shows different colors when viewed from different directions.

5.59 carat (ct) oval tanzanite contrasted with 28 channel set tapered baguettes and 12 round brilliant cut diamonds.

The vault of the evening sky and a field of stars is conjured by this 5.59 carat (ct) oval tanzanite contrasted with 28 channel set tapered baguettes and 12 round brilliant cut diamonds. Courtesy: EraGem.com

Tanzanite history & lore

Tanzanite may be a relative newcomer to the world of colored stones, but it was one of the most exciting gem discoveries of the 20^th century. Blue stones emerging from Tanzania were identified as the mineral zoisite in 1962 by Polish expatriate George Kruchluk. Not until 1967, though, did prospector Manuel D’Souza — with the help of a Masai tribesman — locate the primary source: the Merelani Hills. D’Souza filed four mining claims. Word spread and 90 more claims were quickly registered – even though at the time there was some confusion as to the identity of the gem material.

Tiffany & Co. believed that tanzanite had international appeal and became its main distributor. In 1968, Tiffany launched a major advertising campaign to promote it. With its vivid colors, high clarity and potential for large cut stones, tanzanite quickly became a sensation. Today, it is not only a December birthstone, but it is also the gem for the 24th wedding anniversary.

Where tanzanite comes from

Grass-covered hillsides, scrub brush, rocky soil and an occasional tree form the landscape of the Merelani Hills. In the major mechanized operations there, thousands of workers recover tanzanite from mines dug over a hundred meters deep into the earth. North of the mines tower the snow-covered slopes of Mount Kilimanjaro.

Peeking out from the clouds is the domed summit of Mount Kilimanjaro. Tanzanite is mined in its shadow. Photo: Eric Welch/GIA

Qualities to look for in tanzanite

Color: The most prized color in tanzanite is a pure blue similar to fine sapphire or an intense violet-blue. Tanzanite with a bluish purple body color is also popular, but less valuable. In any hue, pale colors are less prized than saturated ones.

Be mesmerized by the rich color of this 4.91 ct tanzanite, which mimics the deep blue of fine sapphire, and its regal frame of diamonds. Courtesy: 1stdibs.com

Clarity: Tanzanite is usually free of eye-visible inclusions. If any inclusions are present – especially those that pose a durability problem, such as fractures – they typically lower the value.

Cut: Tanzanite is available in a wide range of shapes, but cushion and oval cuts are more common. Because of its pleochroism, cutting direction determines the gem’s overall face-up color. Cutting a tanzanite to emphasize the bluish purple color usually wastes less rough than cutting it to get a pure blue or violetish blue color. The cutter has to make a choice between a smaller top-color gem and a larger bluish purple one.

Carat Weight: Fine tanzanite with a strong, deep color can be found in pieces weighing 5.00 carats or more. Smaller sizes in less saturated colors are commonly seen in mass market jewelry.

Some 17.67 carats of tanzanite blossom in Sir Zoltan David’s magical “Flowerfly” necklace. The piece won the Tanzanite Foundation’s “Be Born to Tanzanite” Competition in 2007. Photo: Robert Weldon/GIA. Courtesy: Zoltan David

Tanzanite treatments, care & cleaning

Tanzanite is stable under normal wearing conditions, which means it’s resistant to the effects of normal heat, light and common chemicals. Still, the December birthstone may crack if exposed to very high temperatures or sudden temperature changes. It can be attacked by hydrochloric and hydrofluoric acids.

Warm, soapy water is always the best way to clean this December birthstone. Ultrasonic and steam cleaners are never recommended for tanzanite.

Untreated, tanzanite is typically brown. Tanzanite is routinely heat treated to modify its color to a predominantly blue to bluish purple. The treatment is stable with no additional durability concerns.

TURQUOISE: THE HISTORIC DECEMBER BIRTHSTONE

A shoreline of diamonds surround an ocean of turquoise in this captivating ring. Courtesy: Arya Esha

Gemological properties of turquoise

Turquoise is found in only a few places on Earth: dry and barren regions where acidic, copper-rich groundwater seeps downward through deeply altered or broken rocks where it reacts with minerals that contain phosphorus and aluminum. The result of this process is a porous, semitranslucent-to-opaque hydrous phosphate of copper and aluminum.

This December birthstone owes its texture to its structure and composition. Turquoise is an aggregate of microscopic crystals that form a solid mass. If the crystals are packed closely together, the material is less porous, so it has a finer texture. Fine-textured turquoise has an attractive, waxy luster when it’s polished. Turquoise with a less-dense crystal structure has higher porosity and a coarser texture, resulting in a duller luster when it’s polished.

Porosity and texture don’t just affect appearance: They also affect the durability of turquoise. This December birthstone is fairly soft—it ranks 5 to 6 on the Mohs scale of hardness. Turquoise with a coarse texture might have poor toughness, too, so it fractures easily. Samples with finer texture have fair to good toughness.

Gemologists love this December birthstone because turquoise often contains matrix: spiderweb-like veins that provide evidence of the rock in which it formed. They also like how turquoise is colored by copper, which creates some of the most vivid blues and greens in the gem kingdom.

Whether opaque, semitranslucent or checkered with spiderwebs, turquoise enchants

Whether opaque, semitranslucent or checkered with spiderweb-like veins, turquoise enchants. Composite photo: Eric Welch, Robert Weldon, Terri Weimer/GIA, Dr. Edward J. Gübelin collection. Courtesy (far right): Barlow’s

Turquoise history & lore

Turquoise has been cherished for millennia. The pharaohs and other rulers of ancient Egypt adorned themselves with it. Chinese artisans carved it more than 3,000 years ago.

This December birthstone was thought to possess many beneficial powers, like guaranteeing health and good fortune. From the 13^th century on, it was believed to protect the wearer from falling (especially off horses), and would break into several pieces at the approach of disaster. Hindu mystics maintained that seeing a turquoise after beholding the new moon ensured fantastic wealth.

Turquoise played an important role in the lives of Native Americans. The Apache thought turquoise could be found by following a rainbow to its end. They also believed that attaching the December birthstone to a bow or firearm made one’s aim more accurate. The Pueblo maintained that turquoise got its color from the sky, while the Hopi thought the gem was produced by lizards scurrying over the earth.

An artisan from the Zuni tribe made this turquoise brooch. Courtesy: 1stdibs.com

Turquoise adorns the funerary mask of King Tut, who ruled Egypt more than 3,000 years ago. It also appears in jewelry belonging to more modern royalty, such as the Jordan turquoise demi-parure (turquoise, diamond and sapphire necklace and earrings) in the collection of Britain’s Queen Elizabeth II. Wallace Simpson (1896-1986), Duchess of Windsor, wore a famous amethyst and turquoise necklace made by Cartier. Turquoise is also the gem of the 11th wedding anniversary.

A dazzling display of color, Cartier’s bib necklace for the Duchess of Windsor features a sea of turquoise cabochons and faceted amethyst. Courtesy: N. Welsh, Cartier Collection © Cartier

Where turquoise comes from

Turquoise has been mined in the Nishapur district of Iran for more than 1,000 years. The even-colored, intense blue turquoise from this region is dubbed “robin’s egg blue,” “sky blue” and “Persian blue.” Trade professionals now use these terms to describe turquoise of this color – regardless of the source.

This is the view on the way to Nishapur. Courtesy: Dr. Edward J. Gübelin Collection

Although New Mexico was the largest producer of turquoise in the U.S. until the 1920s, today most of the U.S. production of this December birthstone comes from Arizona and Nevada. Mines have evocative names like Dry Creek, Easter Blue, Emerald Valley and Fox. The Kingman mine in Arizona is a historically important source that is known for producing intense blue turquoise. Now closed to turquoise mining, the Sleeping Beauty mine was a prolific producer for more than four decades.

The intense blue turquoise beads in this necklace came from Arizona’s Sleeping Beauty mine. Photo: Robert Weldon/GIA. Courtesy: Somewhere In The Rainbow

China is now the world’s largest producer of fine turquoise. Hubei Province, in central China, is the source of most of the gem-quality turquoise currently being mined there.

Qualities to look for in turquoise

Color: The color of turquoise usually ranges from light to medium blue or greenish blue. It’s often mottled, and sometimes it has dark splotches. It might also have veins of matrix running through it.

The most-prized turquoise color is an even, intense, medium blue, with no matrix and the ability to take a good polish. But some consumers prefer a greenish blue, and some contemporary designers seek turquoise referred to as “avocado” and “lime green.”

Clarity: Turquoise can be semitranslucent to opaque. Semitranslucent stones are preferred.

Note the even color in the clusters of turquoise dangling from gold chains in this one-of-a-kind piece. Courtesy: Denise James

Cut: Turquoise is most often fashioned as cabochons. The smoothly rounded dome shape sets off turquoise’s color, texture and any matrix beautifully. In addition, manufacturers and artisans fashion turquoise rough into round or oblong beads for necklaces, and into small, flat pieces that are popular as jewelry inlays. Other rough material might be tumbled into “nuggets” or polished as free-form shapes that reflect the shape of the original rough. There are also examples of top-color blue turquoise engraved with Persian or Arabic inscriptions that are then inlaid with gold.

Carat Weight: Turquoise is available in a wide range of sizes. All sizes, even very small ones, are used in Native American jewelry, and large pieces have been popular for carvings. For any size, the quality and evenness of the color is the overriding value factor.

Rich blue turquoise surrounded by 24K gold makes these earrings a mesmerizing sight. Courtesy: Lika Behar

Turquoise treatments, care & cleaning

A colorless wax or polymer is often used to improve the color and luster of turquoise. Other treatments include applying epoxy to thin turquoise slices to strengthen them, applying coatings of lacquer or epoxy, and filling cavities with imitation pyrite inclusions made of metal-filled epoxy.

It’s safe to clean turquoise jewelry with warm, soapy water, but this December birthstone should never be cleaned with steam or ultrasonic cleaners. Heat or solvents can damage the treated surfaces on some turquoise.

Turquoise is generally stable to light, but high heat can cause discoloration and breakage. Turquoise can be damaged by acids, and it can be discolored by certain chemicals, cosmetics and even skin oils or perspiration.

ZIRCON: THE COLORFUL DECEMBER BIRTHSTONE

A 19.76 ct orangy brown zircon is ringed by 0.51 carats of diamonds. Courtesy: 1stdibs.com

Gemological properties of zircon

Zircon comes in a wide and varied palette of yellow, green, red, orange, brown and blue hues, making it a favorite among collectors and knowledgeable consumers. This December birthstone is 6 to 7.5 on the Mohs scale of hardness.

The zircons in this colorful array originate from Sri Lanka, Cambodia, Thailand, Tanzania and other locations.

Zircon comes in a wide array of attractive colors. Photo: Robert Weldon/GIA, Dr. Edward J. Gübelin Collection.

Colorless zircon is known for its brilliance and flashes of multicolored light, called fire. These two zircon properties are close enough to the properties of diamond to account for centuries of confusion between the two gems.

This 11.41 ct oval blue zircon with its diamond halo is like a lake that invites the viewer to peer into infinity. The tsavorite garnet side stones are leafy touches to the icy scene. Courtesy: Omi Privé

Gemologists love zircon because its radioactive trace elements are a geologic clock that tells us about the early Earth. This December birthstone also has very high luster, high refractive indices (the measure of the extent to which light is bent as it leaves a gemstone at an angle other than perpendicular to the surface) and strong dispersion, which is responsible for the brilliance and rainbow flashes of fire.

Zircon history & lore

The origins of the word zircon have elicited colorful debate. Some scholars believe it comes from the Arabic word zarkun, meaning “cinnabar” or “vermilion.” Others think the source is the Persian word zargun, or “gold colored.” Considering the color range for this December Birthstone, either derivation seems possible.

Zircon comes with pleasing lore. In the Middle Ages, it was thought to lull one into a deep sleep and scare off evil spirits. In the Hindu religion, zircon alternates with hessonite garnet as one of the nine gems of the navaratna. When worn together, the nine gems protect the wearer and bring good health, wealth and wisdom.

Victorians had a fondness for blue zircon. Fine specimens can be found in English estate jewelry from the 1880s.

Regal rings like this show why blue zircon is a popular gem. Courtesy: LeVian

Where zircon comes from

Sri Lanka’s wealth of gems is legendary: Sapphire in various colors, ruby, alexandrite, spinel, tourmaline, moonstone and quartz are some of the gem minerals unearthed there. So is zircon. Elahera, a region in central Sri Lanka, is one of the country’s most productive areas. Mountains, jungles and restless streams make for a dramatic landscape.

An artisanal miner searches for gems in the Elahera region of Sri Lanka. Photo: Vincent Pardieu/GIA

Australia’s Harts Range is known for producing zircons in yellow-brown, orangy brown, pink and purple. Go there and you’ll see open savannahs, dry stream beds and low-lying hills that meet the horizon. Zircon Hill is where the gem is mined. The nearby city of Alice Springs is known for its outback culture, aboriginal art and quirky sporting events like a regatta race held in a dry river bed.

Zircon is often located near sapphire sources. Countries where the two overlap include Sri Lanka, Myanmar, Vietnam, Cambodia and Australia.

Qualities to look for in zircon

Color: Some zircons display warm autumnal earth tones such as yellowish and reddish brown. Red and green zircons have market value as collectors’ stones, and cat’s-eye zircons occasionally appear on the market. There are also colorless zircons.

A brisk autumn day, a fireplace and apple cider would be the perfect backdrop for this ring, which features a 7.96 ct zircon. Photo: Robert Weldon/GIA. Courtesy: Richard Krementz Gemstones

Although collectors clearly love zircon’s variety of colors, consumers seem most enamored of just one hue: blue. Gem dealers report that at least 80 percent of the zircons they sell are blue. Because they’re in greater demand, blue zircons usually command higher prices than any of the other varieties.

A blue zircon takes center stage in the “Reine de Glace” pendant designed by Lisa Krikawa. Courtesy: Krikawa Jewelry Designs. Blue zircon by John Dyer & Co.

Clarity: Zircons are relatively free of inclusions. But many untreated zircons have a cloudy or smoky appearance that, if extreme, can be a negative factor with buyers. In Victorian times, this smokiness made zircon a popular gem for mourning jewelry. Today, most faceted zircon is free of inclusions that are visible to the unaided eye. Eye-visible inclusions cause a drop in zircon value. Rarely, zircon might contain long, parallel inclusions that create a cat’s-eye effect when the stone is cut as a cabochon.

Cut: It’s a challenge to cut zircon because the gem is brittle. Cutters usually fashion zircon in the brilliant style to take advantage of its brilliance and fire. Zircon can also be found in step cuts, which have rows of parallel facets, and mixed cuts, which are a combination of brilliant and step-cut facets.

A richly colored 7.23 ct zircon set in an ornate 18K gold ring looks like it belongs on the finger of European royalty. Courtesy: 1stdibs.com

Carat Weight: The supply of this December birthstone is generally limited, and typical zircon sizes depend on color. Blue or green stones normally range from one carat to 10 carats, with yellows and oranges up to around five carats. Reds and purples are usually smaller.

Zircon treatments, care & cleaning

Warm, soapy water is recommended for cleaning zircon. Ultrasonic and steam cleaners are not recommended for this December birthstone.

Zircon is commonly heat treated to produce blue and colorless varieties, as well as orange, yellow and red. The gem is generally stable when exposed to light, but some heat-treated stones might revert to their original colors (usually light brown) after prolonged exposure to bright light. Exposure to heat can alter the color of some zircon. Zircon is stable when exposed to chemicals.

Because zircon tends to abrade, it is best to avoid wearing it in rough conditions, such as while gardening, playing sports or doing dishes.

The color of the 14.48 ct zircon in this ring evokes a forest … fields … grassy expanses. Courtesy: 1stdibs.com

Ready to go shopping for the December birthstone? Be sure to take our Tanzanite Buying Guide and Turquoise Buying Guide with you when you go!

November Birthstone: What You Need to Know About Topaz and Citrine

November 1, 2017

Those with a November birthstone have two beautiful options to choose from: topaz and citrine. Topaz comes in a rainbow of colors; citrine is known for its charming yellow and orange hues. The two gems give you countless options. Your challenge will be deciding which one to pick. We offer help.

In this post, we cover

Gemological properties of topaz
Topaz history & lore
Where topaz comes from
Qualities to look for in topaz
Topaz treatments, care & cleaning
Gemological properties of citrine
Citrine history & lore
Where citrine comes from
Qualities to look for in citrine
Citrine treatments, care & cleaning

November birthstone: Gemological properties of topaz

The November birthstone topaz has an exceptionally wide color range that, in addition to brown, includes various tones and saturations of blue, green, yellow, orange, red, pink and purple. Colorless topaz is plentiful, and is often treated to give it a blue color.

Pictured here are some of the many colors of topaz, the November Birthstone. From left to right: a 9.21 ct colorless emerald cut, a 15.01 ct light blue emerald cut, a 18.41 ct purplish pink emerald cut and a 12.54 ct orange-red emerald cut.

Pictured here are some of the many colors of topaz. From left to right: a 9.21 carat (ct) colorless emerald cut from Nigeria; a 15.01 ct light blue emerald cut from Brazil; an 18.41 ct purplish pink emerald cut from Pakistan; and a 12.54 ct orange-red emerald cut from Brazil. Photo: Robert Weldon/GIA

Color varieties of the November birthstone are often identified simply by hue name—blue topaz, pink topaz and so forth—but there are also a couple of special trade names. Imperial topaz is typically a medium reddish orange to orange-red though some dealers, especially those in Brazil, apply the term to yellow, pink and red topaz as well. The reddish pleochroic color (pleochroism is the display of different body colors from different viewing directions) of Imperial topaz often appears at the ends of fashioned gems–like pears and ovals–that have an otherwise yellow-to-orange body color. Red is one of the most sought-after (and least available) topaz colors.

Sherry topaz—named after sherry wine—is a yellowish brown or brownish yellow to orange. Stones in this color range are often called precious topaz to help distinguish them from the similarly colored but less expensive citrine and smoky quartz.

Topaz is an 8 on the Mohs Scale of Hardness. It’s not very tough, so a hard blow might split it, and extreme pressure or sharp temperature changes might cause it to break. The November birthstone is best set in a protective mounting like a bezel or used in pieces that aren’t subjected to heavy wear, like pendants and pins.

A pink topaz set in a diamond and platinum butterfly brooch is a delightful sight. Photo: Robert Weldon/GIA. Courtesy: Richard Krementz Gemstones

Gemologists love topaz because it comes in some of the gem world’s largest crystals: The largest are measured in kilos, not carats. They also love the fact that faceted topaz takes such a high polish and is slightly slippery to the touch.

November birthstone: Topaz history & lore

Topaz was long thought to have many benefits. The ancient Greeks believed that topaz gave them strength. From the 1300s to the 1600s, Europeans thought it could thwart magic spells and dispel anger. The November birthstone was also believed to have curative powers. To treat “dimness of vision,” 12^th century abbess St. Hildegard recommended placing topaz in wine for three days and then rubbing the moistened topaz on the patient’s eyes.

Imperial topaz has aristocratic cachet. It is commonly believed that the name originated with the Russian royal family’s insistence on keeping the finest colors of this gem, which was mined in Russia’s Ural Mountains, exclusively for their use. An alternate explanation, especially popular in Brazil, is that it dates from an 1881 visit by Brazilian Emperor Pedro II to Ouro Preto—the town closest to Brazil’s most productive topaz mines–and the gift of a reddish topaz to him. Regardless of the source of the designation, there is no question all believed this beautiful gem was fit for a king.

Want a gem with an aristocratic cachet? Imperial topaz might be the one for you. Photo: Robert Weldon/GIA

Blue topaz is the gem of the fourth wedding anniversary, and Imperial topaz is the gem of the 23rd wedding anniversary.

The artistic carving of this 38.56 ct blue topaz intensifies the color. Photo: Lydia Dyer. Courtesy: John Dyer & Co.

November birthstone: Where topaz comes from

Minas Gerais, a state in Brazil, is one of the most important sources for high-quality topaz. Yellow to orange, red, pink, violet and blends of red with orange or purple are some of the colors unearthed here. The nearby town of Ouro Preto is a fitting companion. In this UNESCO world heritage site, majestic colonial churches checker the skyline and quaint cobblestone streets crisscross the city.

Necklace set with a 24.13 ct fancy-cut topaz and the accompanying 44.11, 71.21 and 66.66 ct loose stones.

Topaz mined from the Ouro Preto region of Minas Gerais, Brazil comes in a lovely range of hues, as displayed in this necklace set with a 24.13 ct fancy-cut topaz and the accompanying 44.11, 71.21 and 66.66 ct loose stones. Photo: GIA and Harold & Erica Van Pelt. Courtesy: Amsterdam Sauer Co.

Northwestern Pakistan is known for producing pink topaz. Ghundao Hill, close to the small town of Katlang, has been mined since 1972. The most sought-after shade of pink topaz from Katlang has a tinge of violet, which some in the gem trade call cyclamen pink. But even at Ghundao Hill, only rarely is fine pink topaz found.

Ghundao Hill, a valley carpeted in green in Northwestern Pakistan, is known for producing topaz the November birthstone.

Ghundao Hill’s setting is quite picturesque: A valley carpeted in green starts at the base. The towering Hindu Kush Mountains rise in the distance. Photo: Dr. Edward J. Gübelin/GIA

Other topaz sources include Namibia, on the western coast of southern Africa, and the gem-rich island of Madagascar. Today, some topaz is also found in the historic Russian localities and elsewhere including, Africa, China, India, Myanmar, Sri Lanka and Vietnam, as well as the United States and Mexico.

November birthstone: Qualities to look for in topaz

Color: Blue topaz and colorless topaz are widely available and very affordable. Most of the blue topaz on the market today has been color treated, as described in the next section. Red and pink topaz varieties are rare, highly cherished and will carry a significantly higher price tag per carat. Imperial topaz is also highly prized.

An 11.11 ct Imperial topaz ring accented with 0.29 carats of rubies and 0.75 carats of diamonds, all set in rose gold.

A royal enchantment: This 11.11 ct Imperial topaz is accented with 0.29 carats of rubies and 0.75 carats of diamonds, all set in rose gold. Courtesy: Omi Privé

Clarity: Faceted blue topaz is almost always free of eye-visible inclusions. Topaz in colors that are not as plentiful may be included. Depending on the rarity of the color, inclusions may not have a significant effect on value.

Cut: Topaz is cut in a wide variety of shapes and styles, including emerald, cushion, oval, pear, round, triangular, marquise and fantasy cuts.

Carat weight: If the color of the topaz is considered rare, the per-carat price may rise dramatically as size increases.

This 1,002 ct fantasy cut topaz is a work of art. Photo: Orasa Weldon/GIA

November birthstone: Topaz treatments, care & cleaning

To clean this November birthstone, do not use steam cleaning or ultrasonic cleaners to clean topaz: Warm, soapy water works best.

Topaz is often treated. Since naturally colored blue topaz is extremely rare, colorless topaz is often processed with irradiation followed, in some cases, by heating to turn it various shades of blue. The three irradiation techniques used are exposure to gamma rays in a cobalt irradiator, bombardment with electrons in an accelerator and bombardment with neutrons in a nuclear reactor. Gems that are treated in an accelerator or nuclear reactor may become radioactive, but the U.S. National Regulatory Commission (NRC) does not allow release of such stones into the trade until radioactivity levels fall below certain limits. The NRC advises that “any dose from these gems would be extremely small” and would continue to go down. Dealers use terms like “London blue,” “Swiss blue,” “super blue” and “maxi blue” to describe darker blues, and “sky blue” for paler hues. In general, darker blues cost slightly more than lighter hues, but both are typically affordable.

A blue topaz that has undergone irradiation to achieve a color result often referred to as “Mystic Topaz” or “Caribbean Topaz”.

This blue topaz has undergone irradiation to achieve this color result often referred to as “Mystic Topaz” or “Caribbean Topaz” by the trade. Photo: Valerie Power/GIA

Also common, is the heating of yellow to reddish brown topaz to create pink gems. Both irradiation and heat treatment are permanent under normal conditions of wear and care. For the most part, they are undetectable.

High heat or sudden temperature changes can cause internal breaks in topaz. The gem’s color is generally stable to light, but prolonged exposure to heat or sunlight might cause fading in yellow-to-brown, reddish brown or dark brown gems. Topaz may be affected slightly by some chemicals.

In addition to irradiation and heat treatment, colorless topaz is sometimes coated with a thin metallic film to change the color or produce a fanciful iridescent effect. The coating can resist daily wear and tear, but abrasive cleaners or buffing wheels will remove it. Only a mild soap solution should be used to clean a topaz treated in this manner.

November birthstone: Gemological properties of citrine

Citrine is the transparent pale yellow to brownish orange variety of quartz. The finest citrine color is a saturated yellow to reddish orange free of brownish tints. Its color comes from traces of iron. However, this November birthstone is actually rare in nature: Most citrine on the market is the result of heat treating amethyst.

Citrine’s attractive color, plus the durability and affordability it shares with most other quartzes, makes it the top-selling yellow-to-orange gem. Gemologists love this November birthstone because it has a modest price tag, and the price per carat does not rise dramatically for larger sizes.

The Jolie Citrine Necklace features 64 graduated bezel-set cushion cut citrines, highlighted by a 177.11 ct pear shaped citrine drop.

The Jolie Citrine Necklace, once owned by American actress Angelina Jolie and now part of the National Gem Collection at the Smithsonian Institution, features 64 graduated bezel-set cushion cut citrines, highlighted by a 177.11 ct pear shaped citrine drop. Courtesy: RP Studio

November birthstone: Citrine history & lore

This November birthstone is a variety of quartz, which has been used in jewelry for thousands of years. The ancient Greeks carved rock crystal ornaments that glistened like permafrost. Roman pontiffs wore rings set with massive purple amethysts and citrine has been reported in Roman jewelry. It was particularly popular in colorful Scottish jewelry from the Victorian era. Citrine, believed to derive from the French word for lemon (citron), is given for the thirteenth wedding anniversary.

A fantasy cut unleashes the fire within this 43.49 ct citrine. Photo: Priscilla Dyer. Courtesy: John Dyer & Co.

November birthstone: Where citrine comes from

The top sources for natural citrine are Bolivia, Spain, Madagascar, Mexico and Uruguay. Amethyst that’s typically heat treated to a citrine color is mined mostly in Brazil.

These citrine and diamond butterfly earrings remind us of the beauty surrounding the Anahí mine in Bolivia. Photo: C. D. Mengason/GIA. Gift of Denoir

Deep in the world’s largest freshwater wetland lies Bolivia’s Anahí mine, an important source for natural, unheated citrine. Fields of wild flowers, brightly plumed birds, kaleidoscopes of butterflies, Howler monkeys and jaguars are some of the actors on this vast stage. The story of the mine is worthy of the setting. Discovered by a Spanish conquistador in the 1600s, it was given to him as dowry when he married Anahí, a princess from the Ayoreos tribe of Paraguay. The mine was lost for three centuries, until it was rediscovered in the 1960s.

The Anahí mine in Bolivia, an important source for the November birthstone citrine.

Cradled between the two mountains lies the Anahí mine in Bolivia. Photo: Robert Weldon/GIA

The Anahí mine produces a unique combination of amethyst and citrine in the same crystal; when the two colors appear together in a fashioned gem, it is known as ametrine. The citrine produced at the Anahí mine typically ranges from orange-yellow to brownish/greenish yellow.

Citrine, amethyst and ametrine gems produced at the Anahí mine in Bolivia.

The Anahí mine produces citrine, amethyst and ametrine gems in a broad range of hues. Photo: GIA & Tino Hammid

November birthstone: Qualities to look for in citrine

Color: The finest citrine colors are saturated, with little to no brown component, and range from yellow to orange-yellow to reddish orange. Look for warm, sunny hues.
Clarity: Citrine is usually “eye clean,” meaning it lacks eye-visible inclusions. Visible inclusions in a pale-colored gem greatly reduce the citrine’s value.
Cut: Citrine is available in a wide variety of standard shapes and cutting styles. In addition, many high-end gem carvers have fashioned the warm yellow gem into unusual fantasy cuts for distinctive jewelry and objets d’art. Citrine rough with minor inclusions is often used to make beads or is used occasionally for cabochons or more conventional carvings.
Carat weight: Citrine crystals occur in a wide range of sizes, and faceted stones up to 20 carats are readily available in jewelry.

A citrine and diamond ring set in 18K gold.

Like an ember, citrine glows in this ring. Courtesy: Arya Esha

November birthstone: Citrine treatments, care & cleaning

Citrine can be safely cleaned with warm, soapy water. While it is usually okay to clean citrine in an ultrasonic machine, steam cleaning is risky since citrine should not be subjected to heat.

As noted above, most of the citrine on the market is the result of heat treatment, which causes some amethyst to change color from an undesirable pale violet to an attractive yellow. In some cases, a darker starting material is used, as the amethyst’s original hue can determine the richness of the resulting citrine’s yellow color.

A 15 ct citrine pendant encircled by 0.30 carats of diamonds.

Spring Bouquet, a pendant made for Rio Tinto’s “Diamonds with a Story” marketing campaign, glows with a 15 ct citrine encircled by 0.30 carats of diamonds. Courtesy: Matthew Campbell Laurenza

Love topaz? Craving citrine? You’ll find our Topaz Buying Guide and Citrine Buying Guide to be extremely helpful.

October Birthstone: What You Need to Know About Opal

October 3, 2017

Opal is the October birthstone – and its play-of-color is so mesmerizing that it borders on magical. From coveted black opal, to serene water opal, to blazing fire opal, there’s one for every taste. We help you find your favorite. (more…)

September Birthstone: What You Need to Know About Sapphire

September 5, 2017

The September birthstone is sapphire – a gem that’s been cherished for thousands of years. Sapphire is one of the most popular colored stones because of its beautiful blues. It also comes in a rainbow of other colors. Here’s how to pick a stunning one.

In this post, we cover:

Gemological Properties of Sapphire
Sapphire History & Lore
Where Sapphire Comes From
Qualities to Look for in Sapphire
Sapphire Care & Cleaning

Gemological Properties of Sapphire

The colors of sapphire enchant. Faceted stones (from left to right): 6.36 carat (ct) pinkish orange “padparadscha,” 1.63 ct pink, 4.76 ct violet, 5.43 ct violet-purple, 3.03 ct blue, 2.12 ct blue, 8.06 ct yellow, 3.46 ct yellow, 2.00 ct orange and 1.01 ct deep orange. Photo: Robert Weldon/GIA. Courtesy: Dr. Edward J. Gübelin Collection and Bill Larson, Pala International

The September birthstone, sapphire, comes in a range of colors in addition to the familiar blue. Called “fancy sapphires,” these are violet, green, yellow, orange, pink, purple, black, brown and intermediate hues. Sapphire can be colorless, too. That’s because the gem belongs to the mineral species corundum, which is composed of aluminum and oxygen. In its purest state, corundum is colorless. However, colorless corundum is rare. Most corundum contains trace amounts of additional elements including iron, titanium, magnesium, vanadium, and chromium that replace aluminum in the corundum structure. The coloration of blue and fancy sapphires involves interactions between these impurity elements—sometimes in combination with imperfections in the gem’s crystal structure—that absorb light and impart color into this otherwise colorless mineral.

Blue in sapphire requires interaction between impurities of iron and titanium, whereas chromium is key to the pink in pink sapphires and the red color of ruby, which also belongs to the corundum mineral species. (Red corundum is the only color not called sapphire – it is called ruby.)

Any color of corundum can show a phenomenon called asterism, or the star effect. This phenomenon usually appears as a six-ray star pattern across a cabochon-cut stone’s curved surface when the gem is examined in direct sunlight or with a single intense light. Asterism is caused by the presence of numerous tiny, needle-like inclusions of rutile or hematite oriented in specific directions.

The star, or asterism, in this 5.43 ct blue sapphire is heavenly. Photo: Robert Weldon/GIA. Courtesy: Fu Gemstone Import, Seattle, WA.

Another interesting variety is color-change sapphire. These fascinating stones appear to be a different color under different lighting conditions, most often going from violetish blue in daylight or fluorescent lighting to deep reddish purple in incandescent light. Their presence adds a special dimension to the options available for the amazing September birthstone.

Pictured here are a cluster of sapphire crystals from Myanmar, a faceted blue-green sapphire from Kenya and a faceted blue sapphire from Montana. Photo: Robert Weldon/GIA. Courtesy: (Rough) Bill Larson, Pala International; (Left) Columbia Gem House; (Bottom) Dr. Edward J. Gübelin collection.

Some of the many colors of sapphire are on display in “Dawn” – a one-of-a-kind necklace that features 450 carats of sapphire beads. Courtesy: Denise James

Sapphire History & Lore

The September birthstone has traditionally symbolized sincerity, truth, faithfulness and nobility. For countless centuries, sapphire has adorned royalty and the robes of the clergy. The elite of ancient Greece and Rome believed that blue sapphires protected their owners from harm and envy. The clergy of the Middle Ages wore sapphires because they symbolized Heaven.

The September birthstone was also reputed to have healing powers. Medieval Europeans believed that sapphire cured plague boils and diseases of the eye. It also was thought to be an antidote to poison.

A dragonfly brooch studded with a 38.82 carats of pink, green, blue and yellow fancy sapphires and 5.74 carats total weight of diamonds might make you believe in the magical powers of the gem. Photo: Robert Weldon/GIA. Courtesy: Pioneer Gems

Famous sapphires include the Rockefeller Sapphire, a 62.02 ct rectangular step cut stone that was unearthed in Myanmar (Burma). Acquired in 1934 by financier and philanthropist John D. Rockefeller, Jr. (1874–1960) from an Indian maharaja, the gem was recut and remounted over the years. The sapphire was first set as a brooch and later as a ring featuring two triangular brilliant cut diamond side stones.

The Rockefeller Sapphire is a 62.02 ct rectangular step-cut sapphire weighing 62.02 ct. Here it is flanked by cut-cornered triangular cut diamonds, mounted in a platinum ring signed Tiffany & Co. Courtesy: Christie’s Images Ltd., 2015

The Starry Night Sapphire is another famous gem. Also originating from Myanmar, the Starry Night Sapphire is a 111.96 ct cabochon-cut gem whose magnificent six-rayed star is a fine example of asterism.

The Starry Night Sapphire comes from Myanmar, one of the most important sources of the gem. The gemological phenomenon asterism is responsible for creating the six-rayed star. Photo: Robert Weldon/GIA. Courtesy: Benjamin Zucker

In addition to being the September birthstone, sapphire is also the gem commemorating the 5th and 45th wedding anniversaries.

Where Sapphire Comes From

Kashmir, Myanmar and Sri Lanka are three historically important sources for sapphire. Significant quantities of the September birthstone have also been found in Australia, Thailand, Cambodia, Madagascar and the United States (Montana), among other countries in Asia and Africa.
Sapphires were discovered in Kashmir around 1881, when a landslide high in the Himalayas exposed a large pocket of velvety “cornflower” blue crystals. As the spectacular sapphires began to appear farther south, the Maharaja of Kashmir—and his army—took control of the new locality. From 1882 to 1887, thousands of large, beautiful crystals were recovered. In this short season of six years rests Kashmir sapphire’s reputation as one of the world’s most coveted gems. Production has been sporadic since then, but auction houses occasionally sell fine pieces of Kashmir sapphire.

A magical pool … a drop of the sky … a slice of eternity. This 3.08 ct cushion cut Kashmir sapphire conjures such visions. Photo: Robert Weldon/GIA. Courtesy: Edward Boehm, RareSource

The Himalaya Mountains are the source of Kashmir’s beautiful blue sapphires. Photo: Robert C. Kammerling/GIA

The Mogok area of Myanmar is another locale famed for producing the September birthstone. Jungle-clad hills hemmed by mountains make a dramatic landscape. Sapphire typically occurs alongside ruby deposits, but in much lower quantities than its red counterpart. ”Burmese” sapphire, as it is still called by many, can possess a rich, intense blue hue, which has made it particularly prized. Myanmar is also a noted source of jadeite jade, spinel, zircon, amethyst, peridot and other fine gem materials.

A scenic view near Mogok rivals the beauty of the sapphires hidden underground. Photo: James E. Shigley/GIA

For more than 2,000 years, Sri Lanka has been a source of fine sapphire. The blue stones mined from the alluvial gravels of this “jewel box of the Indian Ocean” can display remarkable brilliance and saturation. In addition, the island’s milky white “geuda” sapphires can be heat treated to a rich blue color.

Sri Lanka is one of the few sources for padparadscha (from the words for “lotus color” in Sinhalese) sapphires. Poetic descriptions for this light to medium pinkish orange to orange-pink sapphire include “salmon,” “sunset” and ”ripe guava.” Padparadschas are quite coveted and have a very high per-carat value.

This gem-rich island is also home to ruby, spinel, garnet, tourmaline, topaz and many more gems.

Using the same rudimentary washing techniques as generations before them in Sri Lanka, miners search for sapphire among the gravels in a local stream. Courtesy: Afsaneh Tazari

The spellbinding beauty of this 6.66 ct gem from Sri Lanka shows why padparadscha sapphires are so prized. Photo: Robert Weldon/GIA, Dr. Edward J. Gübelin Collection

Thailand is a source of sapphire and a major cutting and treatment center. In dense jungle crossed by dirt roads, miners dig for sapphire in Chanthaburi Province. Sapphires from Myanmar and Cambodia often end up in Chanthaburi for cutting and treatment, and are also sent to Bangkok, an important gem hub.

In the distance, a mining pit dots the tropical terrain of Chanthaburi, Thailand. Photo: Vincent Pardieu/GIA

Sapphire Qualities to Look For

Here are some tips for picking a stunning sapphire.

Color: The value of most sapphires—both blue and fancy color is based on a combination of hue, tone and saturation. Hue is your first impression of a gem’s basic color. Tone is the darkness or lightness of a color. Saturation is a color’s strength or intensity.

Each sapphire color has its own quality variations. In general, though, the more intense the color and the fewer zones of unattractive color, the more valuable the stone. The most highly valued blue sapphires are velvety blue to violetish blue, in medium to medium-dark tones. The saturation should be as strong as possible without darkening the tone and compromising brilliance. Blue sapphires with these qualities command the highest price per carat.

Zoning in sapphires of all colors is common and, especially when apparent in the stone viewed face up, reduces the value of the sapphire. It is important to examine a stone from all angles to determine the presence or degree of zoning before making a purchasing decision.

Other factors that help determine the value of a sapphire are clarity, cut, proportions, rarity and market demand.

These fancy sapphires range from yellow to highly saturated reddish orange.

For those who prefer warm-colored gems, the September birthstone does not disappoint. These fancy sapphires range from yellow to highly saturated reddish orange. Photo: GIA & Tino Hammid. Courtesy: Varujan Arslanyan

Cut: Fashioned sapphires appear most commonly in cushion and oval shapes with brilliant-cut crowns and step-cut pavilions. Blue sapphire cut into trilliant (triangular), emerald, pear and marquise shapes are also available.

The cushion cut is particularly popular for sapphires, like this 4.47 ct blue stone. Photo: Robert Weldon/GIA. Courtesy: Bear Essentials

Asterism in a sapphire will only be revealed if the stone is cut as a cabochon. A finished stone’s attractiveness depends on the star’s orientation and the cabochon’s symmetry, proportions and finish.

Look for a cabochon with a symmetrical outline and a star that’s centered when the gem rests on its base. The dome of the cabochon should be fairly high—about two-thirds of the stone’s width—to focus the star sharply. If it’s too high, the phenomenon loses its graceful motion when the stone is tilted. Excessive height also makes the stone difficult to mount.

Clarity: Sapphires typically have some inclusions. As a general rule, inclusions make a stone less valuable, and the price can drop significantly if they threaten the stone’s durability. Sapphires with extremely high clarity are rare and very valuable.
Carat Weight: Sapphires can range in size from a few points to hundreds of carats. Large blue sapphires are more readily available than large rubies. However, most commercial-quality blue sapphire weighs less than 5 carats. Large padparadscha or color-change sapphires are exceedingly rare.

Sapphires are the stars in these earrings. They were especially popular during the Art Deco era of the 1920s and ‘30s, a look that you can get in an engagement ring. Courtesy: Genevive

Treatments: As you shop, be aware that sapphires are often treated in some way to improve their color and other aspects of their appearance. Heating is one common treatment, particularly for blue sapphires. The results are stable and durable, and heat-treated blue sapphires typically retain their enhanced effects permanently. Because of this, the practice is commonly accepted in the colored stone market.

Lattice diffusion is another common treatment that can improve color. This involves packing a sapphire into a crucible with coloring agents such as titanium or beryllium, and then heating them almost to a melting point. This allows the elements to enter the stone and alter its color. For example, pink sapphires may turn orange or pinkish orange (padparadscha) with beryllium diffusion. While this treatment is also considered permanent, in some cases (such as titanium-diffused blue sapphire) the added color is so shallow it could be removed if the stone was chipped or had to be recut.

A less stable, and relatively less common, treatment is the filling of surface-reaching fractures with oil, epoxy, resin or a high-lead-content glass. In some cases, a colored filler is used.

Sapphires treated with a filler require special care. The filler can be damaged through contact with a variety of chemicals or high heat. Even relatively mild substances like lemon juice can cause alteration of high-lead-content glass.

Be sure to ask if your sapphire has been treated before you buy. A GIA Colored Stone Identification Report will tell you if a stone is natural or synthetic and whether it has been treated in any fashion.

Sapphire Care & Cleaning

The September birthstone is relatively hard, ranking 9 on the Mohs scale. It has excellent toughness and no cleavage, which is a tendency to break when struck. This makes it a great choice for rings and other mountings subject to daily wear.

Corundum is stable under normal wearing conditions, which means it’s resistant to the effects of heat, light and common chemicals. Boric acid powder will etch the surface of even untreated stones. Fracture-filled, cavity-filled and dyed stones can be damaged by even mild acids like lemon juice.

Warm, soapy water is always a safe choice for cleaning the September birthstone. Ultrasonic and steam cleaners are usually safe for untreated, heat-treated and lattice-diffusion-treated stones. Fracture-filled, cavity-filled or dyed material should only be cleaned with a damp cloth.

Now that you know all about sapphire, you’re probably in the mood to buy a beautiful one. Our Sapphire Buying Guide can help you make a great choice.

July Birthstone: What You Need to Know About Rubies

June 30, 2017

Ruby is the July birthstone – and it’s one of the most coveted of gems. Called the “king of gems” in ancient India, today it can command the highest per-carat price of any colored stone. Here’s what you need to know about this beautiful gem.

In this post, we cover:
Gemological Properties of Ruby
Ruby History & Lore
Where Ruby Comes From
Qualities to Look for in Rubies
Ruby Treatments, Care & Cleaning

July Birthstone: Gemological Properties of Ruby

Ruby, the July birthstone, is a variety of the mineral corundum that contains trace amounts of the element chromium, which causes its color. The more chromium present, the stronger the color red. Chromium can also cause red fluorescence, which adds to the intensity of the color. Fluorescence is visible light temporarily emitted by some gem materials when they are exposed to high-energy sources such as ultraviolet light (as in sunlight), X-rays or lasers.

Some rubies form in marble, when heat and pressure act on minerals in limestone. These rubies tend to be highly prized, as they have a higher concentration of chromium and little iron, which is an ideal recipe for a bright red color. They also tend to be highly fluorescent.

Other rubies are found in basalt, which forms when molten lava cools and solidifies. Basalt-hosted rubies typically have significantly more iron than marble-hosted rubies and thus are darker. A higher iron content can also mask the fluorescence, eliminating that extra glow of red color.
Still other rubies form in an amphibole-bearing gneiss (a coarse-grained metamorphic rock). These rubies tend to have good color, though they have more iron than the marble-hosted stones and less than those from basalt.

Gemologists love the July birthstone because synthetic ruby was used to create the first laser in 1960. They also consider chromium to be the “rock star” of trace elements.
Consumers love ruby for its intense red color and because it’s a 9 on the Mohs scale of hardness, just below diamond. As such, it is a very durable stone that holds up well to daily wear in rings and other jewelry.

A look at these earrings featuring 8.16 carats of ruby, 1.78 carats of marquise diamonds, and 1.69 carats of round diamonds shows why we are enchanted by the gem. Courtesy: Omi Privé

July Birthstone: Ruby History & Lore

A prized gem like ruby naturally comes with many attributes. Because it resembles the color of blood, ancients believed it could stop hemorrhaging. The July birthstone was also thought to cure inflammatory diseases and soothe anger. Burmese warriors believed it made them invincible in battle. Medieval Europeans maintained that rubies bestowed health, wisdom, wealth and success in love.

In addition to being the July birthstone, ruby is traditionally given for the 15^th and 40^th wedding anniversaries.

The Harry Winston Ruby Slippers are a famous example of the July birthstone in a spectacular setting. To commemorate the 50^th anniversary of the movie “The Wizard of Oz,” the House of Harry Winston fashioned a pair of red slippers featuring 4,600 rubies weighing an estimated 1,350 carats. When they were created in 1989, they were valued at $3 million.

4,600 rubies weighing an estimated 1,350 carats glitter in the slippers; another 50 carats of diamonds accent the unique creation.

Harry Winston’s famed ruby slippers were exhibited at GIA in December 1997. Some 4,600 rubies weighing an estimated 1,350 carats glitter in the slippers; another 50 carats of diamonds accent the unique creation. Courtesy: Harry Winston

July Birthstone: Where Ruby Comes From

Our search for the July birthstone starts in Myanmar (formerly known as Burma). For more than five centuries, the Mogok area in Myanmar has produced some of the finest rubies – vibrant red beauties softened by light-scattering inclusions and a glowing red fluorescence. The region is a place of weathered marble and ancient Buddhist temples.

Golden spires of a monastery near Mogok are flashes of color along the mountainside. Photo: Robert C. Kammerling/GIA

These ruby crystals intertwined with their matrix rival the beauty of finished gems from Mogok. Photo: Robert Weldon/GIA. Courtesy: Bill and Jeanne Larson

Vietnam is another important source for marble-hosted rubies. The Luc Yen region, where rainforest-clad mountains rise over broad paddy fields, produces rubies of red to purplish red color. Today, artisanal miners work the soil in hopes of finding a gem that will change their fortunes.

A small village sits at the base of the mountains in the ruby-bearing Luc Yen region. Photo: Vincent Pardieu/GIA

Rubies from Luc Yen and other locales in Vietnam star in these four rings and necklace. Photo: Shane McClure/GIA

This fine 4.04 carat (ct) ruby came from Mozambique, the pre-eminent source of commercial and fine rubies. Photo: Robert Weldon/GIA. Courtesy: Evan Caplan, GemFields

Mozambique is an important new, amphibole-related source for the July birthstone. This African nation is home to the prolific mines at Montepuez. Rubies found there have been compared to the famed gems of Mogok.

For many years in the late 1900s, the basalt-related ruby deposits along the border between Thailand and Cambodia were the major source of rubies in the marketplace. Other important producers include Sri Lanka, Tanzania and Madagascar.

Rubies from Madagascar are a bright, slightly orangy red. Photo: Robert Weldon/GIA. Courtesy: Allerton Cushman & Co., Sun Valley, Idaho

July Birthstone: Qualities to Look for in Rubies

Color: Color is the most important quality factor for the July birthstone. The finest rubies have a pure, vibrant red to slightly purplish red color. A color that’s too orangy or too purplish is considered less desirable. The highest-quality rubies have vivid color saturation that is not too dark.
Clarity: People in the trade expect rubies to have at least some inclusions, because inclusion-free rubies are rare. The impact of inclusions on the value of a stone depends on their visibility. Obvious inclusions or inclusions that reduce transparency or brightness can lower a ruby’s value.
Cut: A ruby’s crystal shape dictates its suitability for certain cuts. Ruby crystals often have a flat tabular hexagonal shape, but crystals from some sources may be elongate.
Carat weight: Rubies are available in a wide range of sizes, but fine-quality rubies over a carat are rare and, not surprisingly, very expensive.

This 5.00 ct oval ruby is all the more radiant set in 18K rose gold and encircled by 2.53 carats of round diamonds in the halo and band. Courtesy: Omi Privé

July Birthstone: Ruby Treatments, Care & Cleaning

Using warm soapy water is a safe option to clean ruby, the July birthstone. Ultrasonic and steam cleaners are usually safe for untreated, heat-treated and lattice diffusion–treated stones. Fracture-filled, cavity-filled or dyed stones should only be cleaned with a damp cloth.

Rubies are often heat treated to remove purplish coloration, leaving a purer red. The process can also remove “silk” (minute needle-like inclusions) that can cause a gem to appear lighter in tone and be more opaque. The trade typically accepts heat treatment to enhance color, as the treatment is stable to normal conditions of wear and care.

Lattice diffusion is a technique whereby heat and chemicals are used to diffuse a specific element into a gem to change its color. This treatment, too, is typically stable to normal wear and care.

Fracture filling is when a substance is introduced into surface-reaching fissures to make them less visible and thus improve the gem’s appearance. Common fillers include glass and glass-like substances, polymers and resins, and oils.

A high-lead-content glass is often used to fill fractures in rubies and thus improve their apparent clarity. There are many of these glass-filled rubies in the market, and in some cases the glass literally holds together a highly fractured gem. The glass can be damaged through contact with a variety of chemicals. Even relatively mild substances like concentrated lemon juice can etch the filler.

Dyeing with colored oils and filling small surface fissures with epoxies are other treatments. However, they are not permanent. These treatments need special care.

Always ask if your ruby has been treated before you buy. The Federal Trade Commission requires disclosure of treatments that affect a gemstone’s perceived value. A GIA Identification Report is important in identifying if a stone is natural or synthetic and whether it has been treated in any fashion.

Diamond and ruby bracelet shimmers with 20.56 carats of cabochon-cut rubies from Tanzania.

Reminiscent of the geometric shapes used in Art Deco–era jewelry, this diamond and ruby bracelet shimmers with 20.56 carats of cabochon-cut rubies from Tanzania. Photo: Kevin Schumacher/GIA

Whether or not you have a July birthstone, owning a beautiful ruby is a rare and precious thing. And if you love red gems in general, check out our Red Gemstone Buying Guide – Part 1 and Red Gemstone Buying Guide – Part 2 for some striking alternatives to ruby.

June Birthstone: What You Need to Know About Pearls

June 6, 2017

Coveted for millennia, the June birthstone still reigns supreme as the queen of modern fashion. Elegant, stylish and organic, pearls come in a rainbow of colors and a range of shapes. Our pearl primer will help you choose beautiful ones.

In this post, we cover:
What Is a Pearl?
Akoya, Tahitian, South Sea and Freshwater Cultured Pearls
Pearl History and Lore
Where Pearls Come From
Pearl Qualities to Look For
Pearl Care and Cleaning

Faceted pearls are not your traditional cultured pearls. These avant-garde beauties can have 200+ facets on their surface. Photo: Robert Weldon/GIA. Courtesy: Victor Tuzlukov

June Birthstone: What Is a Pearl?

A pearl is an organic gem that grows inside saltwater and freshwater mollusks. These soft-bodied animals possess one (univalve) or two (bivalve) shells. Mollusks are invertebrates, meaning they lack a spine or vertebrae.

Gemologists divide the June birthstone into two categories:

Natural Pearls: Pearls form without human intervention. When an irritant enters a mollusk, the mollusk secretes a mixture of calcium carbonate and conchiolin (called nacre). Like a protective shell, the nacre covers the irritant. Although used for adornment for thousands of years, today natural pearls are extremely rare and make up only a small fraction of total pearl sales.

Edwardian natural pearl necklace with alternating light and dark pearls

Natural pearls are the focal point in this necklace from the Edwardian era. Photo: Robert Weldon/GIA

Cultured Pearls: These are a product of human intervention. Technicians implant a piece of mantle tissue alone (common for freshwater cultured pearls) or with a mother-of-pearl shell bead (all saltwater) into a host mollusk. The mollusk covers the irritant with nacre, just like a natural pearl. Cultured pearls are raised in pearl farms – saltwater or freshwater operations where the mollusks are cleaned, protected from predators and eventually harvested. Cultured pearls account for the vast majority of pearl sales.

Cultured Pearls: Akoya, Tahitian, South Sea and Freshwater

Scientists estimate there are more than 100,000 different species of mollusks in the world’s waters. However, only a few dozen of these species produce the June birthstone and only about half of them are used to produce cultured pearls. Cultured pearls are classified by the species of mollusks that produce them.

Akoya cultured pearls have an undeniable elegance. Photo: Robert Weldon/GIA

Akoya Cultured Pearls: The saltwater Pinctada fucata oyster produces white and cream-colored cultured pearls, generally between 2 and 11 mm in diameter, with the average being 6 to 8 mm. Akoya cultured pearls are often perfectly round and have a high luster (the light reflected from or near the pearl’s surface). Most akoya cultured pearls are commercially produced in Japan and China.

A necklace showing the many colors of Tahitian cultured pearls

The many different colors of Tahitian cultured pearls are on display in this exceptional necklace, which features 27 cultured pearls that range from 13 to 19 mm. Photo: Robert Weldon/GIA. Courtesy: A Private Collector and Mona Lee Nesseth, Custom Estate Jewels

Tahitian Cultured Pearls: Famous for their exotic, almost luminescent colors, these are the product of the saltwater Pinctada margaritifera oyster, which is native to the islands of French Polynesia. The mollusk produces pearls in bodycolors sometimes described in the trade with names like aubergine (dark grayish purple), pistachio (yellowish green to greenish yellow), or peacock (dark green-gray to blue-gray, with pink to purple overtones). Tahitian cultured pearls generally range from 9 to 14 mm in diameter, most commonly 9 to 11 mm.

Semi-round South Sea cultured pearl necklace with blue sapphire accents

This necklace of semi-round South Sea cultured pearls with blue sapphire accents makes a breathtaking statement. Photo: Robert Weldon/GIA. Courtesy: Atelier Marisa

South Sea Cultured Pearls: The Pinctada maxima oyster is the largest of all saltwater cultured pearl oysters, and it can produce pearls from 8 to 20 mm in diameter; the average is 13 mm. There are two types of Pinctada maxima oysters: silver-lipped and gold-lipped. The silver-lipped oyster produces pearls that are mostly white to silver, sometimes with pink, blue or green overtones. The gold-lipped oyster produces mostly yellow to orangy yellow pearls, called “gold” or “golden” in the trade.

A handful of freshwater cultured pearls in many colors

Pearls come in many colors, like these freshwater cultured pearls from China. Photo: Robert Weldon/GIA

Freshwater Cultured Pearls: From the mussel Hyriopsis cumingii or a hybrid, these pearls are produced primarily in the lakes, ponds and rivers of China. They come in many shapes, sizes (up to about 20 mm) and natural colors, including white, orange, lavender and purple. They are also dyed in a wide array of colors.

Gemologists love the June birthstone because of its luster – the reflection of light off its surface, and from concentric layers of nacre, like light bouncing off a convex mirror. Pearl’s texture also fascinates: Natural and cultured pearls have a slightly rough feeling when rubbed against your teeth, while imitation pearls are smooth. However, gemologists use X-rays to examine a pearl’s inner structure, which allows them to conclusively separate natural from cultured pearls.

June Birthstone: Pearl History and Lore

The origin of pearls fascinated our forebearers. Ancients from the Middle East believed that pearls were teardrops fallen from heaven. The Chinese fancied that the June birthstone came from the brain of a dragon. Christopher Columbus and his contemporaries thought that mollusks formed pearls from dew drops.

Pearls have long been associated with purity, humility and innocence. So it may be said that the June birthstone meaning is “sweet simplicity.” As such, pearls were traditionally given as a wedding gift.

The June birthstone was also thought to have beneficial properties. In the ancient Sanskrit text, the Atharvaveda, pearls were said to bestow long life and prosperity. In Asia, pearls were believed to help alleviate indigestion and hemorrhages. Arab physicians in the 1820s maintained that pearl powder improved eyesight, quieted nervous tremors and eased depression.

One of the most famous natural pearls is the 50.56 carat (ct) La Peregrina. About the size of a pigeon’s egg, the pearl was discovered in the 1500s in the Gulf of Panama. It became a prized possession of European royalty. Richard Burton eventually gifted it to Elizabeth Taylor in 1969; Christie’s New York auctioned it in 2011 for $11.8 million.

A two-strand necklace with 50.56 ct natural pearl pendant, accented with 56 saltwater natural pearls, four cultured pearls, rubies and diamonds

Literally a royal gem, Elizabeth Taylor’s 50.56 ct La Peregrina pearl was owned by eight Spanish kings, from Philip II (1582-1598) to Carlos IV (1778-1808). Cartier set the pearl as part of the pendant in this two-strand necklace that has 56 saltwater natural pearls, four cultured pearls, rubies and diamonds. Courtesy: Christie’s

June Birthstone: Where Pearls Come From

You’ll have to set sail for pristine waters if you want to find the June birthstone. Pearl-bearing mollusks fail to thrive in polluted waters, so pearl farms are usually located far from civilization – and often in breathtaking settings.

Saltwater pearls are grown in many areas around the world. Akoya cultured pearl farms are primarily found in Japan and China, especially along the southern coasts of Guangdong and Guangxi provinces. South Sea cultured pearls are farmed from the northern coast of Australia through Indonesia to the southern coast of Southeast Asia, with large operations in the Philippines as well. The Gambier Islands and the Tuamotu Archipelago, both part of French Polynesia, are two locales where the rich black Tahitian pearls are cultured.

An akoya cultured pearl farm in Ago Bay, Japan

Ago Bay, Japan is one of the most important sites for akoya cultured pearl farms. Photo: Valerie Power/GIA

Freshwater cultured pearls are primarily grown in China, within a 400 mile (644 km) radius of Shanghai.

The breeding waters of a cultured pearl farm in French Polynesia look like a piece of paradise. Photo: Amanda Luke/GIA

Natural pearls have been found in the Arabian Gulf (Persian Gulf) for at least 5,000 years, while divers have been recovering the June birthstone from the Red Sea since 300 BCE. The Strait of Mannar has been providing pearls since 2000 BCE. Starting in the 16th century, during Spanish colonial rule, large quantities of pearls were recovered from the waters off Mexico, Central America and what is now Venezuela. Only small quantities of pearls are found in any of these areas today.

June Birthstone: Pearl Qualities to Look For

As you’re shopping for pearls and comparing quality and prices, keep in mind the seven factors gemologists use to evaluate and describe the quality of the June birthstone. Known as the GIA 7 Pearl Value Factors^TM, they are:

Size: Pearl measurements are stated in millimeters, rounded to the nearest 0.5 mm. All things being equal, the larger the pearl, the greater its value.
Shape: GIA categorizes pearls as one of seven shapes:
- Round
- Near-round (almost round, with minor variations)
- Oval
- Button (symmetrical, circular and flattened)
- Drop (symmetrical, rounded or pear shaped)
- Semi-baroque (not quite symmetrical; an off-round)
- Baroque (has no apparent symmetry and is noticeably irregular)
Color: Pearl color has three components:
- Bodycolor – The dominant, overall color of the pearl
- Overtone – A translucent color that appears to layer over a large area of the pearl’s surface
- Orient – More than one translucent color over the bodycolor, or surface iridescence
Luster: The intensity and sharpness of the light reflected from a pearl’s surface. There are five categories of luster: excellent, very good, good, fair and poor.
Surface: The nature and number of blemishes or irregularities on the pearl. As products of nature, few pearls are completely blemish free. Pearl surface is described as clean, lightly spotted, moderately spotted, or heavily spotted.
Nacre Quality: The thickness and regularity of the nacre. For nacre quality to be acceptable on a bead-nucleated cultured pearl, no evidence of the bead should be visible and there should be no chalkiness.
Matching: This factor applies when evaluating a strand of pearls or a jewelry item with two or more pearls. Excellent matching requires a uniform appearance across all the pearls, with the drill hole on center.

You should also know that cultured pearls routinely undergo treatment to improve their appearance. Some may be color enhanced by heating, dyeing, irradiation and coating. Other treatments include:

Bleaching – To whiten them and create a uniform appearance
Tinting – The use of a red dye to turn akoya cultured pearls pink (also called pinking)
Buffing – Tumbling pearls in a canister (or similar device) to remove surface imperfections

Diamond and Tahitian cultured pearl cluster earrings

Take special care when cleaning pearl jewelry like these diamond and Tahitian cultured pearl earrings. Photo: Robert Weldon/GIA. Courtesy: Mastoloni, New York

June Birthstone: Pearl Care and Cleaning

Pearls are 2.5 to 3.0 on the Mohs Scale of hardness, so they are a comparatively soft gem and require special care. Store them separately from other gemstones and metal jewelry to prevent scratching. Never store pearls in a plastic bag — plastic can emit a chemical that will damage their surface. Always apply perfume, hair products and cosmetics before putting on your pearl jewelry. The best way to clean your June birthstone: Use a soft, damp cloth, ideally after each time they are worn.

Read more tips on how to care for pearl jewelry to keep your watery treasures beautiful.

June is a month for celebrations, be it weddings, anniversaries, graduations or birthdays. And what better way to celebrate than with the June birthstone. From a classic strand of akoya cultured pearls to a single faceted Tahitian cultured pearl, there’s a look for every taste and budget.

Pearls are trending. Five Easy Pieces shows how to wear them with style.

May Birthstone: What You Need to Know About Emerald

May 2, 2017

With spring in full bloom and summer just around the corner, emerald is the perfect choice for the May birthstone. Kings and queens have prized the sought-after green gem for centuries. Here’s how you can pick a breathtaking one.

In this post, we cover:
Gemological Qualities of Emerald
Emerald History & Lore
Where Emerald Comes From
Emerald Qualities to Look For
Emerald Care & Cleaning

May Birthstone: Gemological Qualities of Emerald

Emerald’s green has been the standard by which other green gemstones have been measured for thousands of years. It is the rich green to bluish green variety of beryl, a mineral species that also includes aquamarine and varieties in other colors.

Trace elements that cause emerald’s color include chromium, vanadium and iron. As a general rule, the higher the chromium or vanadium content, the more intense the green color. The more iron present, the greater the degree of blue. When iron content is relatively high, emerald is a bluer green. When iron content is relatively low, the May birthstone is a purer green.

The difference between an emerald and a less-expensive green beryl is a matter of debate among gem experts. Some in the trade describe the May birthstone as any green beryl colored by chromium. However, gemologists, gemological laboratories and most colored stone dealers, think it is incorrect to call a green beryl an emerald when its color is “too light.” There are differences of opinion even in this group about the definition of “too light.” GIA settles the debate by using lab-graded comparison stones to determine if the green color is sufficiently dark and saturated to be called emerald.

Gemologists love the May birthstone for its inclusions. Emeralds from Colombia can have fascinating characteristic inclusions – called three-phase inclusions – that consist of tiny crystals of rock salt, a liquid and a bubble of gas.

The best emerald crystals are also gorgeous flat-topped green hexagonal columns that can rival the beauty of faceted stones.

Weighing in at 47 carats, this rough emerald crystal from the Muzo mine in Colombia is so beautiful that it may put to rest all debates about color. Photo: Robert Weldon/GIA. Courtesy: Jon Sigerman

May Birthstone: Emerald History & Lore

From Egyptian pharaohs to Inca emperors, emerald has enchanted royalty. Cleopatra was known to have a passion for emerald, and used it in her royal adornments. The legendary Crown of the Andes, fashioned in colonial South America, is one example of how the Spanish revered the May birthstone. According to lore, its largest stone—now called the Atahualpa emerald—was taken from the last Inca emperor, Atahualpa, by conquistador Francisco Pizarro. The modern recovery of the Spanish galleon Nuestra Señora de Atocha shows the length generations of treasure hunters would go to recover its sunken loot.

The word “emerald” comes from smaragdos, ancient Greek for a green gem. Roman author Pliny the Elder, who died in the 79 CE eruption of Mt. Vesuvius, wrote in his encyclopedic Natural History that “nothing greens greener.” He also stated that the May birthstone had therapeutic properties that helped gem cutters: “(they) have no better method of restoring their eyes than by looking at the emerald, its soft, green color comforting and removing their weariness and lassitude.” Science now proves this belief: The color green relieves stress and eye strain.

An emerald and diamond necklace totaling 41.97 carats

An emerald necklace sure to soothe the eye, this beauty has 52 emeralds, with a total weight of 32.86 carats, and 160 diamonds, with a total weight of 9.11 carats. Photo: Robert Weldon/GIA. Courtesy: Ismael Daoud

Emerald was also thought to have magical powers. By placing it under the tongue, one could see into the future. Some believed the May birthstone offered protection against evil spells, cholera and malaria. Others thought it made one an eloquent speaker and exposed lovers who made false promises.

Emerald is traditionally given for the 20th and 35th wedding anniversaries.

The Crown of the Andes is set with a 24 ct emerald center and 442 additional emeralds

The Crown of the Andes, now at the Metropolitan Museum of Art in New York City, boasts an impressive 24 ct emerald center stone and 442 additional emeralds set in the golden headpiece. Photo: Dr. E. J. Gübelin/GIA

May Birthstone: Where Emerald Comes From

Colombia has been the source of the finest emeralds for more than 500 years, and they have been the standard by which all others are measured. Three mining sites in Colombia are particularly noteworthy: Muzo, Chivor and Coscuez. Emeralds of slightly different hues are found at each of these sites. Each locality produces a range of colors, but generally speaking, darker tones of pure green emeralds come from Muzo. Emeralds that are lighter in tone and slightly bluish green are associated with Chivor. Slightly yellowish green emeralds are unearthed in Coscuez.

This 38 carat cluster of emerald crystals originated from Colombia’s Muzo Mine. Photo: Robert Weldon/GIA. Courtesy: Ismael Daoud

Chivor, Colombia is the source of this 4.50 ct emerald. Photo: Robert Weldon/GIA

This 88.4 gram emerald crystal cluster is from Coscuez, Colombia. Photo: Robert Weldon/GIA. Courtesy: Gene Meieran

Emeralds are also found in the state of Minas Gerais, Brazil. One of the most productive sites for the May birthstone is the sophisticated Belmont Mine. Capoeirana is another important locality, a rugged region worked largely by independent miners and small-scale operations.

An independent miner holds a rough emerald

An independent miner at the Capoeirana mining area holds a rough emerald. Photo: Eric Welch/GIA

The May birthstone can also be found in Africa. Zambia is a major source, and mines in the Ndola Rural Restricted Area are known for producing emeralds that are bluish green and darker in tone. Pakistan and Afghanistan are important producers as well.

The 240 carats of emeralds in this drop necklace come from Zambia. Photo: Robert Weldon/GIA. Courtesy: Sanjay Chordia, BEACAB GEMS INC.

May Birthstone: Emerald Qualities to Look For

Color: The most important quality factor in the May birthstone is color. Emeralds that are bluish green to green, with strong to vivid saturation and medium to medium-dark tone, are the most coveted. Emeralds that are highly transparent are especially valuable.

Clarity: Emeralds typically contain inclusions that are visible to the unaided eye. Because of this, jewelry professionals and some consumers understand and accept the presence of inclusions in emeralds. Eye-clean emeralds are especially valuable because they’re so rare.

Emerald inclusions are often described as looking mossy or garden-like. They’re sometimes called jardin, which is French for “garden.”

In colored stones, transparency and clarity are closely linked. This is especially true for emeralds. Jewelry professionals generally accept some eye-visible inclusions in higher-quality emeralds. But when the quantity or nature of the inclusions has a negative effect on transparency and clarity, they also dramatically reduce value.

Cut: Emerald crystals are difficult to cut. Almost all rough emeralds have significant fractures (sometimes called fissures) and a gem cutter must work to minimize the effect of those fractures on the appearance of the finished stone.

These inherent fissures make emeralds more brittle than other gems. Consequently, they are vulnerable to damage during cutting, polishing and setting–or even from careless daily wear.
The famous rectangular “emerald cut,” with its beveled corners and two, three or four concentric rows of facets, maximizes the shape and weight of the original emerald crystal. It also helps protect against damage because the vulnerable corners are faceted and provide a comparatively safe place for prongs.

Carat Weight: Fashioned emeralds come in a wide range of sizes. There are emeralds in museums and private collections that weigh hundreds of carats. At the other extreme are tiny emeralds that weigh fractions of a carat.

A 3.69 ct emerald ring with six diamond side stones

Take extra caution when caring and cleaning for emerald jewelry like this 3.69 ct emerald ring flanked with six diamond side stones. Photo: Robert Weldon/GIA. Courtesy: Ismael Daoud

May Birthstone: Emerald Care & Cleaning

Emerald is a 7.5 to 8 on the Mohs scale of hardness, so it is more susceptible to scratching than a diamond, which ranks 10 on the scale. The May birthstone is often treated to improve its color and clarity. Common treatment methods include:

Dyeing: Paler porous or fractured emeralds are dyed green to enhance their color.
Fracture Filling: Oils, waxes and artificial resins are sometimes used to fill surface-reaching fractures in emeralds. The goal is to reduce the visibility of the fractures and improve the apparent clarity. The volume of filler material present can range from insignificant to major; these substances have varying degrees of stability.

Emerald requires some special care; avoid exposure to heat, changes in air pressure (such as in an airline cabin) and harsh chemicals. Never put an emerald in an ultrasonic cleaner. Filled emeralds can also be damaged by exposure to hot water used for washing dishes.

The May birthstone is perfectly suited to the celebration of life blooming everywhere. Now you can treat yourself – or a loved one – to an emerald that captures the exuberance of the season. Learn more about how to pick a beautiful emerald with our Emerald Buying Guide.

April Birthstone: What You Need to Know About Diamonds

April 4, 2017

Diamond does double-duty: it’s the April birthstone and a near-universal symbol of love. So if you were born in April, you have two reasons to adore the gem. Here’s a crash course on it – and tips for picking a beautiful one.

In this post, we’ll cover:
Gemological Information on Diamonds
Diamond History
Diamond Lore
Where Diamonds Come From
Qualities to Look for in a Diamond
Diamond Care & Cleaning

April Birthstone: Gemological Information on Diamonds

The hardest natural material on earth, diamond ranks 10 on the Mohs Scale of Hardness and is the only gem made of a single element: It is typically about 99.95 percent carbon. The other 0.05 percent can include one or more trace elements, which are atoms that aren’t part of a diamond’s essential chemistry. Some trace elements can influence its color or crystal shape. For example, the presence of nitrogen causes diamonds to appear yellow. Boron atoms are often responsible for the color of natural blue diamonds.

Your pulse may quicken admiring this heart-shaped natural Fancy Intense yellow diamond. Photo: Robert Weldon/GIA

The Blue Empress, a 14 carat Fancy Vivid blue diamond.

Say goodbye to the blues when you admire the Blue Empress, a 14 carat (ct) Fancy Vivid blue diamond. Courtesy: Steinmetz Diamonds

Diamonds form under high temperature and pressure that exist only within a specific depth range (about 100 miles; 160 kilometers) beneath the earth’s surface. The conditions are extreme: Temperatures must be between 2102oF to 2192oF (1150 to 1200 0C); the pressure must be between 50 and 70 kilobars – 50,000 to 70,000 times greater than atmospheric air pressure at sea level. Carbon atoms in this environment in the mantle may form diamond.

A diamond’s hardness is due to the way the carbon atoms bond. Diamond’s crystal structure is isometric, which means the carbon atoms are bonded in essentially the same way in all directions. Graphite, a mineral used to make pencil lead, is also made of carbon, but because the molecules bond differently, this mineral is not nearly as hard.

Gemologists love diamonds because they are beautiful – and because many formed more than a billion years ago. Studying these ancient beauties tell us much about our planet.

April Birthstone: Diamond History

Our love for diamonds started in India, where they were gathered from the country’s rivers and streams. Traded as early as the fourth century BCE, diamonds were coveted by the wealthy. Caravans brought Indian diamonds, along with other exotic merchandise, to medieval markets in Venice. By the 1400s, diamonds were becoming fashionable accessories for Europe’s elite.

This 4 ct old mine cut diamond comes from India’s famed Golconda mines. Photo: Robert Weldon/GIA. Courtesy: Sudhir Jain (Fei)

In the early 1700s, as India’s diamond supplies began to decline, Brazil emerged as an important source. Diamonds were discovered when gold miners sifted through the gravels of local rivers. The country dominated the diamond market for more than 150 years.

The first great South African diamond deposits were unearthed in the late 1800s. The 1866 discovery of diamonds in Kimberley, South Africa, marked the beginning of the modern diamond market. Entrepreneur Cecil Rhodes established De Beers Consolidated Mines Limited in 1888 and, by 1900, De Beers controlled an estimated 90 percent of the world’s production of rough diamonds.

At the end of the 1970s, South Africa, the Democratic Republic of the Congo (previously known as Zaire) and the former Soviet Union were the world’s most important rough diamond producers. In 1982, a highly productive new mine in Botswana added to world production, making the country third in the world in total diamond recovery and second in diamond value. Diamond mining expanded dramatically with the discovery of sources in Australia in 1985 and important new diamond deposits in northern Canada in 2000.

A 8.52 ct rough diamond crystal from the Kao Mine, Lesotho, Africa waits to be transformed into a breathtaking faceted diamond. Photo: Eric Welch/GIA. Courtesy: Fusion Alternatives

April Birthstone: Diamond Lore

An anonymous second-century poet believed diamond warded off the evil eye – a malevolent look believed to cause sickness, poverty and even death. Diamond was even believed to have healing powers. Over the centuries, diamond was thought to be an antidote to poison; a protection against the plague; and a boon for longevity, strength, beauty and happiness.

One look at Jason Dow’s spectacular diamond Empress ring will make you believe that the April birthstone is the cure for all ills. Courtesy: Jason Dow

In addition to being the April birthstone, diamond is the gift of choice for the 60th and 75th wedding anniversaries. And, of course, the diamond engagement ring has become a near-universal symbol of love and marriage.

There are many famous diamonds. The Taylor-Burton Diamond, the Cullinan II, the Portuguese, the Jubilee and the Koh-i-Noor are just a few breathtaking examples.

Taylor-Burton 69.42 carat, D color, Flawless pear-shaped diamond.

The Taylor-Burton diamond is a 69.42 ct, D color, Flawless, pear-shaped gem. This April birthstone sold for US$1.05 million in 1969. Courtesy: Mouawad

April Birthstone: Where Diamonds Come From

Diamonds are now mined around the world – from Angola to Zimbabwe. However, the five largest producers of diamonds account for the vast majority of global production.

Top Diamond Producing Countries – 2015

Country	Rough Diamond Production
Russian Federation	41.9 million carats
Botswana	20.7 million carats
Democratic Republic of the Congo	16.0 million carats
Australia	13.5 million carats
Canada	11.6 million carats

Source:The Kimberly Process

Diamond mining in eastern Siberia reads like an adventure novel. The setting: tundra, frigid temperatures and short days. The props: jet engines and explosives used to heat and soften the ice covering kimberlite pipes – vertical, columnar masses of igneous rock that can be a primary source for diamonds. The story line: In 2013, Alrosa, a Russian diamond mining company, estimated that there were 970 million carats still waiting to be found in the frozen tundra.

Diamonds in Botswana lie below the eastern plains of the country. These prolific mines have been a boon to the economy, creating a growing middle class. The country is also a diamond hub, where approximately 40% of the world’s supply of rough diamonds are sorted and valued.

The Jwaneng diamond mine is one of the most productive in the world. Photo: John Hummel/GIA.

April Birthstone: Qualities to Look for in a Diamond

Until the middle of the twentieth century, there was no agreed-upon standard by which diamonds could be judged. GIA created the 4Cs of Diamond Quality – the first, and now globally accepted standard for describing diamonds.

Color: In most diamonds, the term refers to the absence of color. The less color in the stone, the more desirable it is. Differences can be subtle and difficult for the untrained eye to see, but directly impact the overall quality and value of the stone.
Clarity: Is a measure of the amount, size and placement of internal characteristics, called inclusions, and external characteristics, called blemishes. Grades run from ‘Flawless,’ with virtually no inclusions visible under 10× magnification, to ‘Included,’ which contain obvious inclusions.
Cut: Cut does not refer to a diamond’s shape, but to its proportions and the arrangement of its facets and the quality of workmanship. The amount of brilliance, sparkle and fire in a diamond is determined by cut. Cut grades range from ‘Excellent’ to ‘Poor.’
Carat: This measurement describes a diamond’s weight. Generally speaking, the higher the carat weight, the more expensive the stone. Two diamonds of equal carat weight, however, can have very different qualities and values when the other three Cs are considered.M

Three stone diamond ring totaling 15 carats.

This impressive three-stone ring has 15 carats of diamonds, set in platinum. Courtesy: Rahaminov

April Birthstone: Diamond Care and Cleaning

Clean your diamond by wiping it with a lint-free cloth; or use warm water, mild soap and a soft toothbrush or a commercial jewelry cleaning solution. Also have your diamond jewelry periodically cleaned and its setting examined by a professional jeweler to maintain its beauty and integrity over time.

Yellow gold earrings set with rough diamonds.

Rough diamonds have been enjoying their moment in the spotlight. They capture another side of the gem’s beauty. Courtesy: Petra Class

Now that you’ve learned something about diamonds, you’ll be a smarter shopper. And maybe you’ll have a greater appreciation for the April birthstone.

Thinking about buying a diamond? Our diamond buying guide can help you pick a stunning one.

March Birthstone: What You Need to Know About Aquamarine

March 1, 2017

Winter is on the way out; aquamarine is on the way in. The placid hues of the March birthstone are a tranquil antidote to the season’s bluster. Read on to learn more about this gorgeous gem and how to pick a beautiful one.

In this post, we’ll cover:
Gemological Information on Aquamarine
Aquamarine History & Lore
Where Aquamarine Comes From
Qualities to Look for in an Aquamarine
Aquamarine Care & Cleaning

March Birthstone: Gemological Information on Aquamarine

Aquamarine is the green-blue to blue variety of the mineral beryl. (Emerald is the green to bluish green variety of the same mineral.) Most of the aquamarine in the marketplace is a light pastel slightly greenish blue. Traces of iron in beryl’s crystal structure cause aquamarine’s color. Like many beryls, aquamarine may form as large crystals suitable for exceptionally large fashioned gems and carvings.

10,000+ carat Dom Pedro Aquamarine has been described as “the one gem that can rival the Hope Diamond.”

A celebrated attraction at the Smithsonian Institution, the 10,000+ carat Dom Pedro Aquamarine has been described as “the one gem that can rival the Hope Diamond.” Courtesy: Donald E. Hurlbert, Smithsonian Institution

March Birthstone: Aquamarine History & Lore

Aquamarine’s name comes from the Latin for seawater, and ancient mariners claimed the gem would calm waves and keep sailors safe at sea. March’s birthstone was also thought to bring happiness to marriages. Beryl was believed to give the wearer protection against foes in battle and litigation. It was also thought to make the wearer unconquerable and amiable, and to quicken the intellect.

Aquamarine is not only the birthstone for March, the gem is also given as a present on the 19th wedding anniversary. As for famous ones, in 1936 the government of Brazil gave First Lady Eleanor Roosevelt a dark blue rectangular step cut aquamarine that weighed 1,298 carats (ct). It was the larger of two stones faceted from a piece of aquamarine rough that itself weighed an impressive 2.9 pounds (1.3 kilograms). It is now housed at the Franklin D. Roosevelt Presidential Library and Museum in Hyde Park, New York. A celebrated attraction at the Smithsonian Institution is the 10,363 ct Dom Pedro Aquamarine – believed to be the largest faceted aquamarine in the world. The 14 inch (36 centimeter) high obelisk was fashioned by acclaimed German lapidary Berndt Munsteiner using the fantasy cut technique.

The government of Brazil gave this 1,298 ct rectangular step cut aquamarine to Eleanor Roosevelt when she and President Roosevelt visited Rio de Janeiro in 1936. Courtesy: The Franklin D. Roosevelt Presidential Library and Museum, Hyde Park, New York.

March Birthstone: Where Aquamarine Comes From

The Brazilian state of Minas Gerais has been an important source of aquamarine for the past two centuries. Travel there and you’ll find a changing panorama of landscapes: rocky hills, rivers and scrub brush dominate the central and eastern regions; savannahs, forests and streams checker the west; and lush green hills roll southward. Aquamarines are found in primary (hard rock) and secondary (weathered) pegmatite deposits in the eastern portion of the state, near the gem center of Teófilo Otoni.

Disguised as “love doves,” 14K white gold prongs hold a 32 ct cushion cut aquamarine from Brazil. Courtesy: Loretta Castoro Signature Collection

Aquamarine is also found high in the Karakorum foothills of Pakistan. To reach the deposits, miners must climb steep paths to elevations of 9,800 to 13,000+ feet (3,000 to more than 4,000 meters) and work the sides of forbidding cliffs. Below this inhospitable rocky world lie fertile valleys, rushing rivers and small towns. Aquamarine from this area has been described as “water clear.”

Pakistan’s gem-rich Shigar Valley lies between foothills of the majestic Karakoram range.

A sliver of an opening (on the far left) is the entrance to an aquamarine mine. Pakistan’s gem-rich Shigar Valley lies between foothills of the majestic Karakoram range. Photo: Vincent Pardieu/GIA

Aquamarine is also mined in Kenya, Madagascar, Nigeria, Zambia and Mozambique, as well as elsewhere in Africa. U.S. sources include the Mount Antero area of Colorado (it’s the state gem) and California’s Riverside and San Bernardino counties. In addition, aquamarine has been found in China, Myanmar, Russia and Ukraine, among other countries.

March Birthstone: Qualities to Look for in an Aquamarine

Aquamarine is pastel blue, greenish blue or green-blue. The preferred color is a moderate slightly greenish blue to dark blue. Fine stones are an even blue with no bands of color (called “zoning”). Most faceted aquamarines are free of eye-visible inclusions. Aquamarine is readily available in large sizes – with many fine gems 25 ct or greater. Aquamarine can be cut into almost any shape, and is often fashioned as emerald cuts, pear shapes, or round or oval brilliants. It also lends itself well to fantasy cuts.

A delightfully icy look: a 10.06 ct pear shaped aquamarine is surrounded by 72 round diamonds (0.35 carats) that are set in platinum. Courtesy: Omi Privé

March Birthstone: Aquamarine Care & Cleaning

With a hardness of 7.5 on the Mohs scale, aquamarine is durable enough for everyday wear. Caring for the gem is easy. Use warm water, mild dish soap and a toothbrush to scrub behind the stone where dirt can collect. Ultrasonic cleaners and steam cleaning are usually safe options as long as there are no feathers or liquid inclusions in the gem.

Nearly all the blue aquamarine in jewelry is produced by heat treatment of bluish green, green, greenish yellow and even brownish yellow beryl. The process removes the yellow color component and leaves a purer blue hue. The treatment is undetectable and appears to be permanent.

The aquamarine cabochons in this necklace look like drops of water from the Caribbean. Courtesy: Petra Class

The March birthstone aquamarine has it all: It’s beautiful, eye clean, rich in lore and exceptionably wearable. Now you know how to pick one that will become a cherished addition to your jewelry wardrobe.

Born in March? Pisces and Aries are your zodiac signs. Jewelry designers have fashioned some creative pieces, and we’ve found ones for you to enjoy.

February Birthstone: What You Need to Know about Amethyst

February 7, 2017

Amethyst, the February birthstone, has adorned the nobility for centuries. Now it’s in reach of most consumers. Here’s how to pick a stunning amethyst for the king or queen of your heart – or treat yourself to a royal present.

In this post, we’ll cover:
Gemological Characteristics of Amethyst
Amethyst History & Lore
Where Amethyst Comes From
Amethyst Qualities to Look For
Amethyst Care & Cleaning

If this ring with an amethyst center stone seems a bit otherworldly, it’s because it comes from the Galaxy collection by Arya Esha. Courtesy: Arya Esha

February Birthstone: Gemological Characteristics of Amethyst

Amethyst is the purple variety of the quartz mineral species. Its color ranges from a strongly saturated violetish purple to reddish purple in fine quality gems; to weak grayish violet in commercial quality stones. Natural irradiation acting on trace amounts of iron in its crystal structure causes amethyst’s characteristic color. Amethyst also commonly shows color zoning, which often occurs as angular bands of darker to lighter purple. The saturated purple color is typically limited to the tips of amethyst crystals, while the rest of the crystal fades to colorlessness. Cutting an amethyst crystal often produces a few high-quality, deep purple stones and many more low-quality, light-colored stones.

Gemologists and consumers alike love amethyst because it is a beautiful gem that is also affordable. Even fine amethyst can have a modest price tag. Here’s another reason: Amethyst rough comes in fascinating packages. In gem localities like Brazil, amethyst sometimes forms in hollow, crystal-lined geodes so big you can stand in them.

A 22.62 carat (ct) cushion cut amethyst is the dramatic foreground to the amethyst rough behind it. Photo: Robert Weldon/GIA

February Birthstone: Amethyst History & Lore

The name amethyst derives from the Greek amethystos, which means “a remedy against drunkenness,” a benefit long ascribed to the purple gem. It’s no coincidence that methy is the word for wine, typically of a color very similar to that of this gem. Amethyst was also believed to keep the wearer clear headed and quick witted in battle and business affairs. Renaissance Europeans thought it calmed lovers overrun by passion.

Amethyst is the gem traditionally given for the sixth wedding anniversary. Wear it in celebration of your wedding nuptials or as your February birthstone and you’ll be in royal company: Catherine the Great (Empress Catherine II of Russia; 1729–1796) had a penchant for the gem, and decked herself in necklaces, earrings and other amethyst-adorned ornaments. The famous jewelry connoisseur Wallis, Duchess of Windsor (1896–1986) made a memorable statement when she wore a lavish Cartier-designed amethyst bib necklace to a gala in Versailles in 1953.

The Duchess of Windsor’s bib-style necklace boasts 27 step-cut amethysts, one oval faceted amethyst, and a large heart-shaped amethyst in the front, as well as turquoise cabochons and brilliant cut diamonds, all suspended from a rope-like gold chain.

A colorful medley of purple and blue, the Duchess of Windsor’s bib-style necklace boasts 27 step-cut amethysts, one oval faceted amethyst, and a large heart-shaped amethyst in the front, as well as turquoise cabochons and brilliant cut diamonds, all suspended from a rope-like gold chain. Courtesy: N. Welsh, Cartier Collection © Cartier

February Birthstone: Where Amethyst Comes From

Amethyst was as expensive as ruby and emerald until the 19th century, when large deposits were found in Brazil. The country is still an important source for amethyst, and its southernmost state, Rio Grande do Sul, is a particularly productive area. Along with its rich amethyst deposits, the region is also home to vast grassy plains, thick forests, waterfalls, panthers and jaguars.

The Anahí mine in Bolivia is another famous source for amethyst. Hidden in the Pantanál wetlands, the Anahí mine is shrouded in fascinating lore. It was discovered by a Spanish conquistador in the 1600s, given to him as dowry when he married Anahí (a princess from the Ayoreo tribe), forgotten for three centuries, and rediscovered in the 1960s.

A treasure trove of amethyst crystals lines the walls of the Anahí mine. Photo: Robert Weldon/GIA.

The February birthstone is also found in Zambia. The country is a major producer, and the Kariba amethyst mine is an important source. Amethyst mined here tends to be of superb quality with richly saturated colors.

On the left is amethyst from Zambia. On the right is amethyst from Brazil. Photo: Robert Weldon/GIA. Courtesy: Pala International

February Birthstone: Amethyst Qualities to Look For

To pick a stunning gem, consider these tips:

Color: The finest amethyst is a strong purple or reddish purple, with no visible color zoning. Any brownish or bronze-colored tints lower the value dramatically. Amethysts that are a little less saturated in color are usually more affordable than those with more color saturation. A light lilac amethyst is usually much less expensive than an intense purple.
Clarity: Almost all faceted amethyst is eye clean; that is, no inclusions can be seen with the naked eye. Material with eye-visible inclusions is usually cut into beads or cabochons.
Cut: It is not unusual to see faceted amethysts of 10 or 20 carats and even larger. Because the gem is so plentiful, matched sets of faceted amethyst are relatively easy to obtain for bracelets and necklaces. The gem can also be found in a variety of fancy cuts and nonstandard sizes.

A Striking fantasy cut amethyst pendant.

A series of grooves and concave facets breathe movement and life into this striking fantasy cut amethyst pendant. Courtesy: Sonja Kreis Unique Jewellery and Gems

February Birthstone: Amethyst Care & Cleaning

Amethyst is a 7 on the Mohs scale of hardness. This means that it is appropriate for daily use in rings and other jewelry, but over time may show wear and require repolishing. Because amethyst is more susceptible to damage than harder gems such as rubies, sapphires and diamonds, do not store your amethyst jewelry next to these, as they can scratch it.

Heat treatment is the most common technique for improving the color and marketability of natural amethyst. Heat treatment can’t make pale amethyst darker, but it can lighten the color of very dark amethyst and make it more attractive. It can also remove unwanted brownish inclusions in some amethysts. Some amethyst turns yellow–to citrine–with heat treatment.

Heat treating amethyst results in a durable and permanent change in color. However, submitting it to intense heat may render it slightly more brittle than usual, and care must be taken not to damage pointed faceted corners and edges. Note, too, that excessive heat can remove the color entirely, and some amethyst fades with prolonged exposure to strong light. Though the color is stable with normal use, this is not a gem to wear to the beach every day.

Amethyst jewelry can be cleaned with an ultrasonic cleaner or a steamer, but use caution to avoid thermal shock. A soft brush with mild soap is the safest option.

As you shop, you’ll also encounter lab-created amethyst. Having the same chemical properties as its natural counterpart, synthetic amethyst has been manufactured since the 1970s. As manufacturing processes became increasingly sophisticated, it became more difficult for gemological labs to distinguish natural from synthetic amethyst. GIA can tell the difference, but many in the jewelry industry do not request testing because of the expense and time required to determine the origin of what is a comparatively inexpensive gem. Still, merchants are required to tell you if a gem is natural or synthetic.

These gems from the Montezuma mine in Minas Gerais, Brazil show the varied coloration of quartz: untreated amethyst (left), heated green quartz (center) and heated and irradiated violet quartz (right). Photo: Robert Weldon/GIA. Gift of Henrique Fernandes and Gabriel Freitas, Pinkstone International, Governador Valadares, Brazil.

Amethyst has enchanted kings and queens for many centuries. Now you know how to buy a royal gift for your love with a February birthday. And for some quick tips, take along our Amethyst Buying Guide the next time you go shopping.

January Birthstone: What You Need to Know About Garnet

January 3, 2017

Lucky you if yours is the January birthstone. A favorite gem of the Victorian era, garnet comes in a palette of beautiful colors. Read on to gain a deeper appreciation for the gem and the knowledge to shop more wisely.

In this post, we’ll cover:
Types of Garnets
Garnet History & Lore
Where Garnets Come From
Qualities to Look for in a Garnet
Garnet Care & Cleaning

January Birthstone: Types of Garnets

Garnet is a group of minerals that have the same crystal structure but slight differences in chemical composition. Five members of this group are commercially important as gems:

Pyrope (purple to orangy red)
Almandine (purple to orangy red)
Spessartine (oranges and yellows)
Grossularite (colorless to yellow, to reddish orange and orangy red, to vibrant green)
Andradite (yellow and yellowish green)

There are also mixtures of these five species, creating even more colors. Variations in trace elements such as iron, manganese, chromium and vanadium produce the kaleidoscopic color range of garnets.

An array of the many colors of garnet, featuring yellow, orange , deep pink, reddish orange, green, and bluish green.

These are some of the many colors of garnet (top row, from left to right): 16.94 carat (ct) yellow garnet, 19.89 ct orange spessartine, 44.28 ct deep pink rhodolite, 16.99 ct reddish orange garnet, and 7.26 ct green tsavorite. Bottom row, left to right: 8.20 ct greenish yellow garnet, 12.36 ct golden yellow garnet, 9.22 ct pink garnet, 14.53 ct light green grossular, and 4.32 ct bluish green garnet. Photo: Robert Weldon/GIA

Gemologists love garnets for many reasons. For some, it’s the challenge of categorizing new garnet varieties. Others are fascinated by the characteristics of specific varieties. For example, demantoid garnets, the green variety of andradite, may display dramatic horsetail inclusions, which are one of the few internal clarity characteristics that can increase a gem’s value. Gemologists also love demantoid’s dispersion, which is so high that a well-cut gem displays an amazing amount of fire.

Image of horsetail inclusions in a green demantoid.

It’s obvious how horsetail inclusions got their name. Think of them as Mother Nature’s signature in this green demantoid. Photo: John I. Koivula/GIA

This 7.00 ct demantoid from Russia shows why some garnets are so coveted. Photo: Robert Weldon/GIA. Courtesy: Pala International

January Birthstone: Garnet History & Lore

Red garnets have a rich history. Necklaces studded with them adorned the pharaohs of ancient Egypt. Signet rings in ancient Rome featured garnet intaglios that were used to stamp the wax that secured important documents. The clergy and nobility of the Middle Ages had a preference for them.

The Smithsonian’s antique pyrope hair comb is one of the most famous pieces of garnet jewelry (pyrope is from the Greek pyrōpos, which means “fiery-eyed”). A large rose-cut garnet sits at the crest, much like a queen serenely surveying her court. The pyrope garnets that decorate this tiara-like jewel came from the historic mines in Bohemia (now part of the Czech Republic), and these rich red beauties were extremely popular during the Victorian era (1837-1901), when this piece was fashioned.

Antique pyrope hair comb with a crescendo of red garnet.

A crescendo of red, this antique pyrope hair comb would have made a breathtaking statement when worn. Courtesy: Chip Clark, Smithsonian Institution.

Curious about garnet’s reputed health benefits? Red gems like garnet were thought to be remedies for inflammatory diseases, and to soothe the angry heart. Garnet also was thought to cure diseases of the liver.

18K gold Art Nouveau era pin depicts a dragon or gryphon with a red garnet in its mouth.

This fanciful 18K gold pin depicts a dragon or gryphon with a red garnet in its mouth. It was made during the Art Nouveau era (1890-1914). Photo: Eric Welch/GIA. Courtesy: Jana Miyahira-Smith.

January Birthstone: Where Garnets Come From

Russia and Bohemia were important sources of garnet in the 19th century, when they were prized by the Russian royal family and used by the great jeweler Peter Carl Fabergé (1846 – 1920). Tanzania and Namibia are important present-day sources for garnet. The gem is also found in Myanmar, Brazil, Kenya, Iran, Afghanistan, Pakistan, India and Sri Lanka, among other countries.

The rolling hills of Green Dragon mine in Namibia.

Namibia’s rolling hills are the scenic backdrop to the Green Dragon mine – an important modern source for demantoid garnet. Courtesy: Green Dragon Mine

January Birthstone: Qualities to Look for in a Garnet

Here are some helpful tips on selecting a beautiful garnet:

Clarity: Garnet clarity depends on its type. The red garnets almandine, pyrope and rhodolite (a pyrope-almandine) typically do not have eye-visible inclusions. Some of the orange garnets, like spessartine and hessonite (a variety of grossularite), often have eye-visible inclusions. You can use this information to rule out particular gems. For example, you might not want to purchase red garnets that have eye-visible inclusions.
Cut: Many garnets are cut into standard shapes and sizes for easy setting into jewelry. This is especially true of many red garnets. Expensive garnets like fine-quality tsavorite (a variety of grossularite) are cut into shapes and cutting styles that allow more of the weight to be retained from the rough.
Demantoid is often cut to allow the best possible display of its fire. Garnets are also popular for designer cuts and carvings. Red garnets are classic materials for cutting into cabochons and beads. They are commonly found to have high clarity and to be very transparent.
Carat Weight: Garnets can be found in all sizes and weights. Some garnets, like demantoid and tsavorite, are more commonly found as small crystals, so their value goes up significantly with size. Other garnets, like almandine, occur as larger crystals, so there’s no dramatic rise in value as size increases.

Most garnets are more affordable than diamonds, rubies, sapphires and emeralds. This means you should be able to get a larger gem for the same price.

A 6.22 ct spessartine necklace is encircled with 0.40 ct of round diamonds set in platinum and 18K rose gold.

A 6.22 ct spessartine flaunts its beauty in this necklace. Encircling the fiery orange garnet are some 0.40 ct of round diamonds set in platinum and 18K rose gold. Courtesy: Omi Privé

January Birthstone: Garnet Care & Cleaning

The different types of garnet range between 6.5 and 7.5 on the Mohs scale of hardness. This means that garnets are more susceptible to damage than rubies, sapphires and diamonds. So while not all garnets are good candidates far daily wear in a ring, they are ideal for earrings, brooches and pendants.

Give thought to where you store garnet jewelry in your jewelry case. If you let it rub against harder gems–again, think diamonds, rubies and sapphires–it can be scratched.

Garnets might rarely be treated by fracture filling, which is a method of concealing surface-reaching breaks in the gem by filling them with a glass-like substance. Their comparative affordability may be a reason why garnets are infrequently treated. Regardless, warm soapy water is always safe for cleaning garnets. Ultrasonic cleaners are usually safe, except for stones that have fractures or have been fracture-filled. Steam cleaning is not recommended.

A 5.55 ct oval tsavorite garnet ring, with two fancy yellow diamonds weighing a total of 0.71 ct, and 136 round diamonds weighing 1.02 ct total weight, set in platinum.

This award-winning ring by Omi Privé may just take your breath away. It features a 5.55 ct oval tsavorite garnet, two fancy yellow diamonds weighing a total of 0.71 ct, and 136 round diamonds weighing 1.02 ct total weight, set in platinum. Courtesy: Omi Privé

Whether you’re shopping for the January birthstone, or a gem to celebrate your 2^nd wedding anniversary, be sure to download our Garnet Buying Guide. It has the essential tips you need to find the perfect garnet. Take it with you, and shop with confidence.

GIA 4Cs Diamond Blog