Professional Gemologist Certification Course
Gemstone Visual Examination Quizzes
If you’ve missed it, try taking this sample gem identification quiz, too.
Examining a Rough Gemstone: Quiz 1
You’ve received a piece of rough to identify. First, you clean it carefully. Next, you give it a thorough visual exam, using your unaided eyes, a loupe, and a microscope. In the process, you note the following bits of visual information.
1. What optical feature do you see here?
2. What physical feature do you see here?
3. In the following picture, what inclusions do you find?
4. What kind of inclusions can you see in the following picture?
Rough Gemstone Visual Examination Advice
Some people have difficulty determining the identity of rough material. Although the process is the same for identifying cut material, you often won’t have a refractive index reading to guide you. However, you’ll still usually gather enough information with which to work.
Find a Place to Start
Look at the rough pictured in Question 1 again. All but the most novice gemologists know that purple coloring and strong zoning are common to amethyst. While this piece certainly looks like an amethyst (a quartz variety), you…
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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