Optics: 0 = 1.606; e = 1,608,
Occurrence: ln the Alai Range, Tajikistan, platy masses up to 10 X 7 X 4 cm, in a vein pegmatoidal body compositionally like an alkalic granite.
Also occurs at the Wessel Mine, Karuman, North Cape Province. South Africa.
Comments: Sogdianite is an extremely rare mineral, suitable for cabochons. The color is striking and the material is hard enough to take a good polish. It is usually mixed with other minerals, so the SG and hardness are variable. Chemical analysis may be required to differentiate sogdianite from sugilite, but the latter is far more abundant.
Name: From Sogdiana, the name of an ancient state in Middle Asia.