Lapis Lazuli of Sar-E-Sang (Badakshan, Afghanistan)

摘要

The lapis lazuli deposit of Sar-e-Sang, in Badakshan, Afghanistan, has furnished the raw material for precious objects manufactured since the earliest civilizations. The mine, which is located in the Hindu Kush Mountains, is always difficult to reach, and is open for only a few months during the summer. The lenses mined are included in very hard cipolins in which calcite and dolomite are intimately associated with silicates such as diopside, scapolite, and forsterite. Pyrite is always present. These minerals, with calcite, occur in varying quantities along with the pure mineral, lazurite, in the lapis lazuli, whose color varies with the amount of impurities it contains. Wellformed crystals with the dominant (110) form are rare. An explanation of the genesis of lapis lazuli is proposed. 17 references, 1 figure. (ERA citation 10:007554)