Gemmological and Mineralogical Characteristics of Nephrite from Luodian, Guizhou Province

A new kind of nephrite deposit has been discovered in Luodian County，Guizhou Province recently.In order to verify the mineral components of the nephrite from Luodian，Guizhou Province，this paper investigates this kind of nephrite samples by using the ICPMS，XRD and FTIR.The results show that the nephrite from Luodian，Guizhou Province is mainly composed of tremolite with minor calcite veins and glaebule chert.The refractive index and density of the nephrite samples，quite close to those of the standard tremolite，are generally lower than those of the nephrite from Hetian，Xinjiang.Based on the SEM observation，the tremolite in the nephrite samples from Luodian，Guizhou Province has fibrous texture，columnar texture and sheet－like texture.The characteristics of fine grains and compact structure make the nephrite samples have good process properties.The result of XRD slow scanning shows that the crystallinity of the tremolite in the nephrite samples from Luodian，Guizhou Province is comparatively high，which are probably related with a stable crystalline environment.