THE COMPOSITION OF PYRITE IN VOLCANOGENIC MASSIVE SULFIDE DEPOSITS AS DETERMINED WITH THE PROTON MICROPROBE

Pixeprobe analysis of pyrite from Australian volcanogenic massive sulfide (VMS) deposits indicate significant levels of Cu, Zn, Pb, Ba, Ag, Sb, Bi (from inclusions), As, Tl. Mo, Au, In, Cd (from nonstoichiometric substitution), Co, Ni, Se and Te (from stoichiometric substitution). Pyrite in massive sulfide lenses is enriched in trace elements compared to that in the stringer zone owing to hydrothermal recrystallization. Metamorphic recrystallization also ''cleans'' pyrite of trace elements. High Au values occur in pyrite with high As content. Pyrite in stringer zones is enriched in Se relative to the overlying massive sulfide tenses and the surrounding alteration zones.