Jewelry Metals 101: Gold, Silver, and Platinum
Gold, silver, and platinum are the most commonly used jewelry metals. Learn about their physical properties, alloys, and history.
Diamond Rarity, Quality, and Cost
Word is out that diamonds aren’t that rare. So, why are they still so expensive? Learn about diamond rarity and quality and how they impact cost.…
Destructive Hot Point Testing
Hot point testing can determine if some gem materials are plastic imitations. It can also reveal if a stone is treated with wax or plastic. By Donald…
Determining Optic Figure and Sign Using a Polariscope
Testing for optic figure and sign is an important technique for gemstone identification. You’ll need a polariscope and a condensing sphere.…
Determining Optic Character and 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…
Measuring the Refractive Index of Cabochons
Step 3: Practical Gemology Lesson 5 Back to syllabus You can use a refractometer to determine the refractive indices (RI) of most cabochons and…
Essential Tools for Gemology
Gemology involves studying the optical and physical properties that make gems such unique little treasures. Gem identification involves analyzing…
Why Do We Need Tools for Gemology?
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…
Is a VS1 Clarity Diamond a Good Buy?
Does a VS1 clarity diamond offer a good balance between quality and price? Learn how to compare clarity grades so you can pick a good eye-clean ring…
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