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Buying Gems: Test Your Identification Skills


When buying gems, gemologists must temper their excitement with an analytical eye. Test your gem identification skills with these quizzes.

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Buying Gems, Quiz 1: Pawn Shop Finds

You find yourself at a pawn shop with your loupe as your only tool. You look at four stones, all priced at $25.

Which stones would make a good purchase at that price?

First Stone: Maybe Emerald?

The first stone you pick up looks like an emerald. It has rich, green coloring (better than these photos show) and weighs close to a carat.

First, you examine it face up, with overhead lighting.

green stone face up

Next, you examine the pavilion with overhead lighting.

green stone pavilion

When you hold the stone to a window for backlighting, you see this.

green stone backlit

Is this gem worth the price?

Second Stone: A Medium Blue Gem

Your second pawn shop stone has blue coloring with a medium tone. You’re thinking topaz, but it could be any of a number of other stones, too. It’s nearly eye-clean. When light hits it from the proper angle, it sparkles just a little. You judge its weight at a carat and a half or a little better.

First, you inspect it face up, with overhead lighting.

blue stone face up

Next, you hold the stone up to a window for backlighting….


Donald Clark, CSM IMG

The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters “CSM” after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff’s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book “Modern Faceting, the Easy Way.”

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