Selective depth analyses of the alteration products of bornite, chalcopyrite and pyrite performed by XPS, AES, RBS
Pratesi, Giovanni; Cipriani, Curzio
European Journal of Mineralogy Volume 12 Number 2 (2000), p. 397 - 409
published: Mar 29, 2000
manuscript accepted: Nov 22, 1999
manuscript received: Oct 26, 1998
ArtNo. ESP147051202016, Price: 12.80 €
Abstract The comparative application of three complementary surface analytical techniques allows us to investigate the alteration process and to probe selectively, as a function of depth, the oxidation products of bornite, chalcopyrite and pyrite. Starting from a pristine surface, the samples have been studied at different stages of alteration up to a strongly oxidized state after two years of air exposure. In spite of their different compositions, some similarities exist in their oxidation: iron sulfates seem to be mainly responsible for the increase of alteration whereas copper sulfide layers, due to iron depletion from the subsurface area, act as a barrier to the progress of alteration.