Gem-A education: How to use the polariscope
9:48
Gem-A Education: How to use the refractometer
8:20
Discover the Hidden Stress of Materials with a DIY Polariscope
15:08
Unboxing a Gemologist's Spectroscope
13:10
How to Check Blue Sapphire Beryllium Diffusion Treatment using Water Immersion Technique
18:09
Easy Gem Tests Gemologists Actually Use
6:38
Gemstones go to Disco?! [ Polariscope Tutorial ]
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How to Classify a Lead Glass–Filled Ruby by GIA
8:07