摘要
海沟金矿床是一个大型的沉积变质—热液矿床。自然金是矿床主要的金矿物,它主要富集于自然金—硫化物阶段。自然金的晶形多呈各种形态的显微金分布于硫化物、碲化物及石英的粒间或裂隙中。它的比重大,其晶胞参数与纯金接近。金的成色高并且变化小,成色的高低与矿物组合有关,但矿化深度和温度对它的影响不大。金的颜色指数随成色的变化而变化。自然金的矿物学特征与矿床成因类型有密切关系。
The Haigou gold deposit is a large--sized metamorphosed sedimentary hydro-thermal deposit. Native gold is a main gold mineral of the deposit. It occurs indendritic, elliptical, lath-shaped and allotriomorphic granular forms in the intersticesor cracks of sulfides, tellurides and quartz. The granules are tiny, about 0.001-0.08 mm in size. The fineness of gold is rather high, in the range of 873--1 000.The fineness bears close relation with mineral assemblages, but the mineralizationdepth and temperature have little influence on it. Specific gravity of native goldD= 19. 34--19. 46; micro--indentation hardness Hv= 64.5 kg/mm^2(load 25g ); the celldimension α_0= 4.06667-4.07495 × 10^(-10)m. The color index of native gold is related tothe fineness.With decreasing fineness, the excitation purity P. also decreases, but thevisible reflectance R_v increases accordingly. Therefore, it is possible to estimate thegold fineness if one can accurately measure the color index of gold.
出处
《地质论评》
CAS
CSCD
北大核心
1992年第5期467-473,共7页
Geological Review
关键词
自然金
金矿床
矿物学
native gold
fineness
gold deposit
Haigou in Jilin province
