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…
Phenomenal Gems – Unique Phenomena in Gemstones
Some optical effects in gemstones, such as color, brilliance, and dispersion, can be quite impressive. However, not all optical effects are considered…
Appraising Gems and Jewelry
Step 6: Appraising Lesson 2 Back to syllabus Appraising gems and jewelry involves giving an opinion of value. If you take a pair of earrings to a jewelry…
An Introduction to Gemstone Grading
Although gemologists look at color, clarity, cut, and carat to evaluate both diamonds and colored gems, they must judge these qualities in the…
Evaluating Gemstone Cutting: The Five Ps
Step 4: Gem Grading Lesson 3 Back to syllabus In recent decades, something remarkable invaded the thinking process of the colored stone industry.…
How to Grade Set Gemstones
Step 4: Gem Grading Lesson 4 Back to syllabus Few gemologists deal strictly with loose stones. Occasionally, most may have to grade set gemstones.…
Recutting Diamonds and Colored Gemstones
As a professional gemologist, you’ll grade and value gems. Occasionally, you’ll come across a stone that may need recutting. However,…
Grading Gem Carvings
Gem carvings vary widely in size, shape, and quality. You can find small, simple carvings with a glued-on bail for just a couple of dollars. Fine…
Clarity Grading for Colored Gemstones
Don’t underestimate the importance of clarity, one of the Four Cs of gemstone grading. For faceted gems, basic clarity grading involves…
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