Refractometer Guide, Part 1: Refractive Index Testing

Step 3: Practical Gemology

Lesson 4

refractive index testing - refraction
“Refraction” by Zátonyi Sándor. Licensed under CC BY-SA 3.0.


Gemstone identification is like detective work. You gather clues and eliminate suspects until you’re left with clues that lead to only one suspect … or gemstone. Since few gems share the same refractive index or RI, testing an unknown gem’s RI is a good way to start an investigation. The gem refractometer is the most straightforward and accurate tool …

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