吉林通化集安蛇纹石质玉的矿物成分与成因分析

吉林通化集安地区发现了储量较大的蛇纹石质玉石矿床.X射线荧光光谱分析(XRF)显示蛇纹石质玉石中Si O2含量为35.21%~37.18%,Mg O 46.94%~49.72%,Fe O/Fe2O3之比在0.174~0.685之间.XRD分析显示在0.733 nm、0.366 nm和0.250 nm处存在有利蛇纹石的特征衍射峰.集安蛇纹石质玉主要矿物为利蛇纹石,并常含有镁橄榄石.红外光谱显示在3 650~3 700 cm-1、950~1 100 cm-1、400~700 cm-1存在有特征的利蛇纹石吸收峰.本玉石矿床属区域变质型蛇纹石矿床,利蛇纹石应为橄榄石在低温条件下水热蚀变的产物.

Mineral composition and genetic analysis of Ji'an serpentine jade, Tonghua, Jilin Province

A large new serpentine jade deposit was found in Ji''an area, Tonghua City, Jilin Province. The results of X-ray fluorescence spectrometry show that the content of SiO₂ is from 35.21% to 37.18% in weight percentage, MgO from 46.94% to 49.72%,, the ratio of FeO/Fe₂O₃ is in the range of 0.174~0.685, respectively. The analyses of XRD indicate that there are characteristic peaks at 0.733 nm, 0.366 nm, 0.250 nm, which are attributed to lizardite. The main mineral of the serpentine jade is lizarite, commonly with forsterite. The characteristic XRD peaks of frosterite, dolomite, brucite also occur in the X-ray diffraction spectra. The IR spectra of 3 650~3 700 cm, 950~1 100 cm, 400~700 cm^-1 are found in the serpentine. The Ji''an serpentine jade deposit was formed by regional metamorphism,, lizardite was the product of forsterite hydrothermal alteration under the low temperature condition.