Green Gemstones: History, Lore and Gemology | GIA Knowledge Sessions Webinar Series
1:09:59
Microfeatures of Gems: Geologic Implications | GIA Knowledge Sessions Webinar Series
1:08:31
Red Gemstones: History, Lore and Gemology | GIA Knowledge Sessions Webinar Series
1:05:21
Sapphires: From Ceylon to Ethiopia | GIA Knowledge Sessions Webinar Series
54:04
The Latest Discoveries from Gems & Gemology | GIA Knowledge Sessions Webinar Series
1:03:33
Emerald Sources: The Grass is Greener on the Other Side | GIA Knowledge Sessions Webinar Series
14:38
A brief history of powerful gemstone amulets | V&A
1:15:46
X-Rays and Their Use in Gemology | GIA Knowledge Sessions Webinar Series
18:26