Gemology: Corundum 1
18:29
Gemology: Corundum Ruby 2
12:54
Gemology: Gem Deposits 2
55:31
Hilde Cronwright - Kimberlite indicator minerals and microdiamond techniques for diamond exploration
20:04
Emmanuel Fritsch: “‘Boehmite Needles’ in Corundum Are Rose Channels”
20:42
ALL ABOUT COLORLESS GEMS | SAPPHIRE, BERYL & MORE
18:38
Gemology: Corundum Sapphire 4
26:37
Discover the Hidden World of Ruby and Sapphire!
10:47