"绿豆岩"组分新析

在重庆北碚代家沟乡河犀洞新发现一处厚约１．５０ｍ的绿豆岩，豆粒大小为２～５ｍｍ。经分离检测分析表明：豆粒存在于伊利石中，伊利石的纯度为９５％～９７％；对豆粒采用盐酸溶解、Ｘ－射线衍射和扫描电镜能谱分析表明：豆粒由石英和方解石组成，石英含量在８０％左右，方解石含量约为２０％，石英主要分布于豆粒的表面，而方解石则分布于豆粒的中心。

NEW ANALYSIS ON THE COMPOSITION OF "MUNG BEAN ROCK"

A layer of so-called Mung Bean Rock was recently discovered at Hexidong in Daijiagou, Chongqing. The formation is about 1.5 m thick, in which many hard grains with diameter ranging from 2-5 mm can be easily seen. Compositional analyses show that the rock consists of illitic claystone, with an illite content of 95 -97%. X-ray refraction and SEM examination reveal that the main constituents of the grains are quartz (80%) and calcite (20%). This discovery provides not only a new site to investigate Mung Bean Rock, but also a potential industrial resource of illite.