Abstract

LOPEZ, Luciano  and  ECHEVESTE, Horacio. Paragénesis mineral del depósito tipo five element Purísima-Rumicruz, Jujuy. Rev. Asoc. Geol. Argent. [online]. 2012, vol.69, n.4, pp.537-543. ISSN 0004-4822.

The Purísima-Rumicruz district is located in the eastern limit of Puna, 25 km northeastern of Abra Pampa town, Jujuy. It consists of polymetalic veins containing sulfides of Cu and Pb with minor Ni, Co, sulfarsenides and scarce pitchblende. Vein are hosted by folded interbeddded black shales and sandstones of Acoite Formation. Veins have breccia texture with multiple stage of re-brecciation. The hipogene alteration is weak or absent, however oxidation and supergene enrichment is strong. Overgrowths, replaces, mirmequitic textures, and crystal corrosion are the more frequent mineral textures. The paragenetic sequence shows several stages, the first stage is sulfide rich with high concentration of Cu and Pb with quartz and carbonates, the second records sulfarsenides and scarce pitchblende, with carbonates; the third is copper iron rich sulfides with carbonates and late stage barite. The fourth stage is characterized by supergene enrichment that produced covellite and, finally, the fifth stage consist of malachite, azurite, iron oxides and calcite in thin veinlets and as open spaces infill. This mineralogical assemblage and the paragenetic sequence allow classifying it as a Five Element Deposit.

Keywords : Ore paragenesis; Polymetallic veins; Five Element Deposit; Purisma-Rumicruz district.

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