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…
Diamond Cut Grading, Part 1
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…
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.…
Choosing, Rating, and Grading Diamonds
The most popular gems in jewelry today are diamonds. Their great brilliance and dispersion (the ability to take white light and display flashes…
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,…
Diamond Buying and Carat Weight
When diamond buying, people often ask: which of the Four Cs of gem grading — color, clarity, cut, and carat — is most important. If you’re…
Introduction to Diamond Simulants
Step 4: Gem Grading Lesson 10 Back to syllabus Distinguishing diamonds from their lookalikes is a prerequisite to diamond grading. Assigning…
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…
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