Unusual Phenomenal Colored Stones | GIA Knowledge Sessions Webinar Series
1:05:05
Playing the Blues: An Overview of Sapphire Treatment | GIA Knowledge Sessions Webinar Series
1:26:52
A Comparison of Diamonds and Colored Stones | GIA Knowledge Sessions Webinar Series
19:39
All About Phenomenal Gemstones: Star Sapphire, Labradorite, More!
1:11:32
Gem-A Live: Understanding Gemstone Species and Varieties
58:48
Understanding the Origin of Natural Diamonds | GIA Knowledge Sessions Webinar Series
7:52
The Origins of Alexandrite & The Color Change Effect
1:05:08
Interesting Discoveries from the GIA Laboratory | GIA Knowledge Sessions Webinar Series
55:06