Un modèle minéralogique et chimique du dépôt de l'or dans le gisement de la mine de Salsigne (Montagne-Noire)

In the Salsigne deposit most of the gold was introduced by an aqueous solution of low salinity and deposited at about 250° C within preexisting sulphide-bearing bodies. A quantitative model for the fluid-mineral interaction demonstrates that a significant amount of gold can be deposited as a result of a decrease in both H 2 S activity and oxygen fugacity produced by the alteration of pyrrhotite into pyrite and that of bismuth into bismuthinite as well as by the dissolution of iron-bearing silicates (biotite).