Gem-A education: How to use the polariscope
9:48
Gem-A Education: How to use the refractometer
15:08
Unboxing a Gemologist's Spectroscope
9:52
How to find Stress Patterns with Polarizing Filters
18:09
Easy Gem Tests Gemologists Actually Use
3:53
How to Use the Polariscope
13:10
How to Check Blue Sapphire Beryllium Diffusion Treatment using Water Immersion Technique
11:46
How do you KNOW what a gem is? [Refractometer Tutorial]
27:47