Aquamarine & Co | Colour Mechanisms and Enhancements in the Beryl Group
46:00
Tourmaline as a Gemstone
27:43
Thus Spoke the Stone
42:59
The analytical challenges in testing melee-sized diamonds and coloured stones
43:40
Innovations in responsible sourcing of gemstones: an update from East Africa
52:38
Gem-A Live: In Discussion with Brendan Laurs, Volume 37, No.3
9:48
Gem-A Education: How to use the refractometer
19:47
SSE13 - WORKSHOP AXIS 1 - Julien HENRY
52:01