Tips on Gem Identification for Jewelers

People often ask me about gem identification. More specifically, they ask me to identify their gems. Some think I can do this simply by looking at the gemstones. Sometimes, I can. However, identifying gems is rarely that easy. In most cases, attaching the correct name to a gem requires some detective work.

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Gem Identification 101: The Case of the Red Stone
Let’s say someone asks me to identify a red stone. (“Is this a ruby?” is the form that question usually takes). Now, I should know a ruby when I see one, right? Well, sometimes I can be pretty sure if it’s a ruby or not just by a quick observation. However, I can’’t tell if it’s natural or synthetic without a more detailed analysis.

Narrowing the List of Suspects

To identify this red stone, I’m going to need something more useful than color and transparency. The most helpful information I can have are the properties known as refractive index and specific gravity. If I know one of these, the list of gems that could have that property is immediately reduced to a dozen or two. If I know both of these, the list may well be under ten possible gems.

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The Art of Gem Identification

There is a point where identifying gems becomes an art. The final determination is made by human observation, combined with knowledge and experience, rather than measurements taken with precision instruments. This is especially true when it comes to separating natural from synthetic gems.

A Little Gemology is a Dangerous Thing
If you’re a novice gemologist, I hope you’ve learned two things from this brief introduction. First, the basic procedure for gem identification involves ascertaining a gem’s properties and narrowing your list of suspected identifications down to one. Second, and most importantly, a little knowledge can be a dangerous thing.


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