Evaluating Gem Color: Hue, Tone, and Saturation
What color is the gem on the left? If you answered red, you’re wrong. It’s orange. Most people think the color of the gem on the right…
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…
Advice for Determining Gemstone Value
Step 4: Gem Grading Lesson 9 Back to syllabus Many new gemologists buy low-quality gems believing they’ve found a real bargain. However,…
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…
The Art and Science of Identifying Gemstones
Trigon inclusions are part of a natural, uncut diamond’s original crystal structure. These were photographed on the surface of a rough…
Disclosing Enhancements: A Gemologist’s Guide
Disclosing enhancements is one of the most important responsibilities gemologists face. In fact, many countries are passing stricter laws…
Gemology Cheat Sheets
Use these gemology cheat sheets to review color and clarity grading, as well as special information on diamond and opal. You can also review basic…
Gemstone Examination Lesson
Step 3: Practical Gemology Lesson 28 Back to syllabus While preparing this lesson in gemstone examination, I was in the process of professionally…
Buying Gems: Test Your Identification Skills
Step 3: Practical Gemology Lesson 30 Back to syllabus In this set of gemstone identification quizzes, I’m placing you in a familiar situation.…
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