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…
Basic Gem Appraisal Terms: What is Value?
Step 6: Appraising Lesson 1 Back to syllabus Many people assume that a jewelry or gem appraisal sets a definitive price for an item. Actually, the…
Carats and Gemstone Grading
Step 4: Gem Grading Lesson 2 Back to syllabus A carat is the standard unit of measurement for weighing gems, and it’s one of the Four Cs of gemstone…
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.…
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…
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…
Difficult Gemstone Separations
Step 3: Practical Gemology Lesson 27 Back to syllabus While some gems are fairly easy to distinguish, others present greater challenges to gemologists.…
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