Chalcopyrite disease in sphalerite: pathology and epidemiology.

P. B. Barton; P. M. Bethke

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USGS · 70014184

Chalcopyrite disease in sphalerite: pathology and epidemiology.

P. B. Barton·P. M. Bethke

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Abstract

This descriptive paper identifies three widely occurring textures designated as 'watermelon', 'dusting' and 'bimodal' that characterize the replacement of original Fe-bearing sphalerite by an aggregate of chalcopyrite and low-Fe sphalerite as an integral part of the mineralization process. Replacement probably predominates over alternative modes of origin for small chalcopyrite blebs in sphalerite from most vein and sea-floor massive sulphide deposits that formed in the 200-400oC temperature range and that have not been subsequently subjected to higher T. Sphalerite from the epithermal Ag-Pb-Zn deposit at Creede, Colorado, displays a rich variety of features ("bead chains') that are primary crystal dislocations decorated by exsolved chalcopyrite.-J.A.Z.

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P. B. Barton, P. M. Bethke. 1987. Chalcopyrite disease in sphalerite: pathology and epidemiology.. https://pubs.usgs.gov/publication/70014184

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