Madagascar corundums ( Sapphire & Ruby
© 2004 gggems.com All rights reserved. AL2O3 Sapphire found in a metamorphized limestone. · Crystallographic properties of corundum: Trigonal.c = 1,3630 pp 0 86°4' ; pa1 = 122°26' Macle according to p (1011), often polysynthetic, accompa...英国华人论坛