Refractometer Guide, Part 3: Determining Optic Character and Recognizing Optic Effects
Step 3: Practical Gemology Lesson 6 Back to syllabus Optic character is another useful clue in gem identification. This property exists in every…
Polariscope Guide, Part 2: Testing For Optic Figure and Sign
Testing for optic figure and sign is an important technique for gemstone identification. You’ll need a polariscope and a condensing sphere.…
HPHT Diamond Update
Step 2: Advanced Gemology Lesson 8 Back to syllabus In 1999, General Electric (GE) introduced a new diamond treatment into the jewelry trade. The…
Natural Rubies Clarity Enhanced with Leaded Glass
Prior to 2006, most lead glass filled rubies contained only a very small percentage of glass in surface-reaching fractures to improve clarity.…
What is a Gem?
Step 1: Introduction to Gemology Lesson 2 Back to syllabus For thousands of years, people have used terms like “gem” and “gemstone”…
A Guide to Gem Classification
Little is simple and straightforward in gemology. Every established principle has an exception. This applies to gem classification as well.…
An Introduction to Gem Identification
People often ask me about gem identification. More specifically, they ask me to identify their gems. Some think I can do this simply by looking at…
Recommended Gemology Tools and Instruments
Gemology involves studying the optical and physical properties that make gems such unique little treasures. Gem identification involves analyzing…
Lapidary Fundamentals: Cabochon Cutting
Cabochon cutting or cabbing is the most popular form of gem cutting. Although it requires a fair amount of skill, almost anyone can master this technique.…
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