Study on Compositions and Texture Characteristics of Nephrite from Qinghai Province

Nephrite deposits in Qinghai Province have occurred in contact belt between intermediate-acidic intrusive rocks and dolomite-marble. The main mineral of Qinghai nephrite is tremolite. Using the X-ray powder diffraction, the electronic probe, etc, the mineral compositions and chemical compositions of the nephrite are analyzed. The texture can be systematically classified as the six types: the felt-like texture, the micro-fibrous cryptocrystalline texture, the micro-fibrous texture, the micro-leaf-like cryptocrystalline texture, the micro-leaf-like texture and the radiated fibrous texture.