How to Measure an OTL Gemstone Refractive Index
Measuring “over the limit” (OTL) refractive indices can help distinguish diamonds from simulants. You can do this with a simple upgrade to…
32 Green Gemstones: From Everyday Durability to Collector’s Rarities
A favorite color for nature-inspired designs, green gemstones never go out of style. Learn which of these 32 green gems hold up best for engagement…
Faceting Equipment Essentials
What faceting equipment do novices need to learn to cut gems? Learn what faceting machines, laps, books, and supplies are most suitable for beginners.…
Gem Origin Opinions: When Gemology Labs Agree to Disagree on Sapphire Origins
Why do gemology labs sometimes have different gem origin opinions, especially for sapphires? Learn the science and history behind the debate.…
Gemstones That Make Money
What kinds of gems can novice faceters cut to make a profit? Learn which gemstones make money reliably and which ones have limited potential.
10X Loupe for Gemologists and Jewelers
The 10X loupe is the gemologist’s best friend. Learn how to examine gemstones for fractures, inclusions, color, and much more with this simple…
Should You Cut the Gem Pavilion First?
Experts might successfully cut gems crown first, but cutting pavilion first is usually the best and most practical method. Read this article to…
Gem, Mineral, and Rock Scanner Identification Apps Review
How accurate are gem, mineral, and rock scanner identification apps? Our review covers the strengths and weaknesses of over 20 apps.
Gemstone Faceting Terms: A Glossary for Students
A glossary of frequently encountered gemstone faceting terms for the student gemologist. Our list covers gemology, gem cutting, and equipment.…
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