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Learning how to conduct a gemstone examination takes practice. Follow an expert gemologist step-by-step through tests of five unknown samples.…

A dichroscope can distinguish the colors of pleochroic gems. Learn how gem cutters can use this tool to choose the best faceting designs for these…

Ultraviolet testing can be crucial for gemstone identification. Learn the basics of this technique as well as how to make your own UV viewing box.…

Although gemstone magnetism isn’t a commonly tested gemstone property, it may be useful for making quick separations outside the lab. By Richard…

Step 2: Advanced Gemology Lesson 2 Back to syllabus The optical properties of gems attract our eyes and can give a cut stone a unique character. However,…

Gemstone identification typically starts with measuring a specimen’s refractive index (RI) and specific gravity (SG). These two tests…

The polariscope is one of gemology’s simplest and most useful tools. With a little practice and our three-part polariscope guide, you’ll…

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…

In a recent phone interview, gemology tools expert Cara Williams of Stone Group Labs discussed the myriad tools available to gemologists today.…