Refractometer Guide, Part 2: Cabochon Testing
Step 3: Practical Gemology Lesson 5 Back to syllabus You can use a refractometer to determine the refractive indices (RI) of most cabochons and…
Gemstone Magnetism: The Forgotten Property
Although gemstone magnetism isn’t a commonly tested gemstone property, it may be useful for making quick separations outside the lab. By Richard…
Gemstone Optical Properties
We tend to take light for granted. It’s such a common thing we experience every day. Rarely do we think of the scientific definition of light…
A Beginner’s Guide To Common Gemstone Heat Treatments
Gemstone heat treatments can turn mediocre pieces into items of great beauty. Heating a gem to a specific temperature and then cooling it is a common…
Gemstone Radiation Treatment
Most gems on the market today receive various treatments to change their natural colors and create more desirable, salable products. Radiation…
Identifying Inclusions Found in Enhanced Gems
Gemstone treatments can have a significant impact on the value and stability of a stone. The following enhancement processes leave behind some…
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.…
10X Loupe for Gemologists and Jewelers
The simple 10X loupe fits in your pocket and costs less than any other piece of gemological equipment. You’ll learn more with it than any other…
Lapidary Fundamentals: Gemstone Faceting
Step 1: Introduction to Gemology Lesson 16 Back to syllabus Gemstone faceting is a marvelous amalgam of engineering and art. Through a mechanical…
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