Diamond News
Did you know that tourmaline, one of the October birthstones, crystallizes in the trigonal system and...
GIADid you know that tourmaline, one of the October birthstones, crystallizes in the trigonal system and is the only common gem mineral that forms as three-sided prisms? Learn more: http://bit.ly/2NCXDjl Photo: Orasa Weldon/GIA. Gift of Carl Booth