Multi-stage introduction of precious and critical metals in pyrite: A case study from the Konos Hill and Pagoni Rachi porphyry/epithermal prospects, NE Greece

Mavrogonatos C, Voudouris P, Zaccarini F, Klemme S, Berndt J, Tarantola A, Melfos V, Spry PG

Research article (journal)

Abstract

The Konos Hill and Pagoni Rachi porphyry-epithermal prospects in NE Greece are characterized by abundant pyrite that displays significant textural and geochemical variations between the various ore stages. It is commonly fine-grained and anhedral in the porphyry-related mineralization (M- and D-type veins), while it forms idiomorphic, medium- to coarse-grained crystals in the late, epithermal style veins (E-type). Porphyry-style pyrite from both prospects is characterized by an enrichment in Co, Se, Cu, and minor Zn, and a depletion in other trace elements, like Bi., Mo, Ag, etc. Pyrite in epithermal-style mineralization is mostly characterized by the presence of As, Bi, Pb, Ni and Se. Gold in pyrite from all mineralization stages, occur as a non-stoichiometric substituting element, and its abundance correlates with As content. Arsenic in pyrite from Konos Hill records an increase from the porphyry stage to the epithermal stage (along with gold), however, at Pagoni Rachi, the highest Au and As contents are recorded in D-type pyrite and in the epithermal stage. The composition of the studied pyrite, marks changes in the physico-chemical conditions of the ore-forming fluids and generally follows the geochemical trends from other porphyry-epithermal systems elsewhere. However, a notable enrichment of Se in theporphyry-style pyrite here is a prominent feature compared to other deposits and can be considered as an exploration tool towards Au-enriched mineralized areas.

Details zur Publikation

Release year: 2020
Language in which the publication is written: English