泰山玉玉化程度与化学成分的关系浅析

Analysis on the Relationship between the Degree of Transformation and Chemical Composition in Taishan Jade

摘要:

泰山玉是近年来在泰山西麓作为玉矿勘查并开发的一种蛇纹石质玉石，赋存于镁质超基性岩变质成因的蛇纹岩体中。矿区共有4个矿体，按玉化程度不同，组成矿体的蛇纹岩可分为碧玉、墨玉、未玉化蛇纹岩。通过对不同矿体和不同玉化程度的矿石进行系统采样分析，按玉化程度（碧玉、墨玉、未玉化蛇纹岩），对其主要化学成分的变化进行了系统对比，发现玉化进程中SiO2含量与TFe和LOI含量的变化呈负相关性，即随着玉化程度的提高，SiO2含量增加，TFe和LOI含量减少，呈现出TFe和LOI主要被SiO2置换的特征，使蛇纹岩到玉石由不透明逐渐变得透明，颜色由灰黑—黑色变为较鲜艳的深绿、黄绿等更美丽的色彩,玉质变得更加细腻油润，玉石硬度得到提高。

Abstract:

Taishan jade is a kind of serpentine jade which was found in the west foothill of Taishan mountain in recent years. It occurred in the serpentine pluton in the metamorphic origin of magnesian ultrabasic rocks. There are 4 ore bodies in the mining area. According to mineralization degree of the jade, Taishan jade can be divided into jasper, black jade and unjaded serpentinite. Through sampling analysis of different ore bodies with different degrees of mineralization, according to different degrees of mineralization, the change of chemical components has been compared systematically. It is found that the content of SiO2 is negatively correlated with the content of TFe and LOI in the process of mineralization. Accompanying with the increase of the degree of jademineralization, the content of SiO2 will increase, and the contents of TFe and LOI will decrease. It is showed that TFe and LOI are mainly replaced by SiO2. With the replacement from serpentinite to jade, it becomes more transparent gradually, the color becomes more beautiful from dark gray and balck to dark green and olivine, the quality becomes more smooth, and the hardness increases.