Professional Gemologist Certification Course
Gemstone Identification Quizzes: Testing Procedures
Based on the given test results, try to determine what testing procedures would help you identify the specimen most efficiently. You’ll also have chances to consider how your choices can affect your customer relationships.
Quiz 1: Diamonds and Emeralds?
A customer brings you this piece of jewelry and wants you to identify the stones. In particular, she wants to know if the green center stone is an emerald. She’s willing to pay for a complete examination and wait for its completion.
On examining the ring, you see it’s stamped 14K HGP (heavy gold plate).
The Side Stones
The two colorless, baguette-cut side stones show no identifying features. Due to their position, you can’t put them on a refractometer. The setting prevents light from entering the pavilions of the side stones. Still, you try to test them from the side in a polariscope. The results aren’t clear.
1. What should you do next to identify these side stones?
The Center Stone
The center stone measures 4.1 x 6.3 x 3.1 mm. A loupe examination shows it’s well-cut and polished, with a vitreous luster and some very small inclusions.
With a microscope, you can see a fine…
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.”
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.
Get Gemology Insights
Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!