Contrary to what many people may think, the word “synthetic” does not mean fake when it comes to gemstones. The term actually comes from the Greek word for “to put together.” People “build” or, more accurately, “grow” synthetic crystals. They do this by using chemicals that, given the proper environment, arrange themselves into crystals of essentially the same structure as crystals that grow without human intervention.

A synthetic gem is a man-made material with essentially the same chemical composition, crystal structure and optical and physical properties as the natural gem material.

The two most basic facts about synthetic gems are:

  • Although they are the result of processes that approximate conditions that exist in the earth, they are products of the laboratory, not nature.
  • Their physical, optical, and chemical characteristics are the same as those of their natural counterparts.

The composition and structure of a laboratory-grown synthetic ruby, for example, are essentially the same as those of a natural ruby. The synthetic ruby weighs the same as a natural ruby of equal size. There are, however, slightly different characteristics between the two, including tell-tale inclusions and growth patterns. Gemologists rely on these differences to identify synthetic from natural.

Learning about the most common types of synthetics will help you better understand why they vary in price and in quality. It’s important to remember that most people can’t distinguish between synthetics and stones mined from the earth. So when considering the purchase of any costly gemstone, it’s smart to request a reputable third-party diamond report, like GIA’s, to be sure about what you’re paying for.

Stay tuned for a four-part series on how synthetic stones are created, their relative value and how they should be sold in the marketplace.

Photo provided by GIA and Tino Hammid