Color Grading Fancy Colored Diamonds
Step 4: Gem Grading Lesson 14 Back to syllabus Diamonds come in every color of the rainbow. Our standard white diamonds are either colorless or tinted…
Grading Set Stones
Step 4: Gem Grading Lesson 4 Back to syllabus Few gemologists deal strictly with loose stones. Occasionally, most may have to grade set gemstones.…
How to Grade Fancy Cut Diamonds
“Fancies” — fancy shape or fancy cut diamonds — can have any finished shape other than round. Some well-known examples include princess,…
Identifying Synthetic Diamonds
Step 5: Advanced Gem Information Lesson 2 Back to syllabus Synthetic diamonds aren’t new. General Electric (GE) has been making them since…
Spotlight on HPHT Treatment
Step 2: Advanced Gemology Lesson 8 Back to syllabus In 1999, General Electric (GE) introduced a new diamond treatment into the jewelry trade. The…
Properties of Diamond Simulants
Diamond simulants often appear in jewelry, as side stones and accents as well as centerpieces. Identifying these lookalike materials, whether…
Introduction to Diamond Treatments
Even as new diamond treatments enter the market, old techniques are revised and improved. Learn how to identify the most common current treatments.…
Lab-Created Diamonds: the Ultimate Guide
Lab-created diamonds have an undeserved stigma. However, they make excellent, lower cost alternatives to natural, mined diamonds. In this article,…
How To Evaluate Diamond Symmetry
Gemologists must often evaluate diamond symmetry, and a rigorous evaluation requires a proportion scope. This device projects the image of the…
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