The problem of mineral association and mineral paragenesis in ore deposits has been the subject of much discussion. The attempts at a rational explanation have, however, been largely unsuccessful since they were not based on sound physical-chemical principles. A new attempt is made in this paper, and it is shown that the temperature and the fugacity (f) of O, S and CO 2 in ore-forming fluids at the time deposition of the vein minerals largely control the mineralogy of ore deposits. fs 2 -fo 2 -T diagrams showing the stability fields of sulfides, oxides, and sulfates of nineteen metals are developed as well as fs 2 -fo 2 -fco 2 diagrams showing the stability of these compounds and of carbonates of the respective elements. The diagrams are based on recent compilations of thermochemical data; they are used in the second paper of this series to define the approximate composition of ore-forming fluids and the relationships between temperature, pressure, and mineralogy in hydrothermal ore deposits.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not have access to this content, please speak to your institutional administrator if you feel you should have access.