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…
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,…
Distinguishing Diamonds: Educating Your Eyes
Step 4: Gem Grading Lesson 10 Back to syllabus Distinguishing diamonds from their lookalikes is a prerequisite to diamond grading. Assigning…
Clarity Grading Diamonds
Step 4: Gem Grading Lesson 12 Back to syllabus When clarity grading a diamond, gemologists examine anything that interferes with the free passage…
Color Grading White Diamonds
Step 4: Gem Grading Lesson 13 Back to syllabus “White,” 14kt white gold ring set with one 1.05-ct diamond and 6 10-pt diamonds, by Mark Somma.…
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…
Traditional Diamond Cut Grading Methods
Of the Four Cs of gem grading, cut ranks as the most important for diamonds. The cut (or make) determines why one diamond features spectacular fountains…
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