Original scientific paper

Pyritized bauxites from Minjera, Istria, Croatia

Boris Šinkovec ; Faculty of Mining, Geology and Petroleum Engineering, University of Zagreb, Pierottijeva 6, Zagreb, Croatia
Krešimir Sakač ; Croatian Natural History Museum, Demetrova 1, Zagreb, Croatia
Goran Durn ; Faculty of Mining, Geology and Petroleum Engineering, University of Zagreb, Pierottijeva 6, Zagreb, Croatia

Abstract

Pyritized bauxite was exploited in the valley of Mirna river in Istria already 400 years ago. It was used as a raw material for production of vitriol and alum. The pyritized bauxite contains both pyrite and marcasite. The conditions of their formation are interpreted in terms of the pH of the micro-environment and the concentration of sulfur and iron. Two phases of pyritization of bauxite have been recognized. Sulphur from the first phase of pyritization originated from organic matter of hangingwall sediments, while during the second phase sulfur mainly originated from the sea water. Pyritization is in some places accompanied by diasporization.

Keywords

pyritized bauxite; diaspore; Paleogene; old bauxite mining; Minjera; Istria

Hrčak ID:

307250

URI

https://hrcak.srce.hr/307250

Publication date:

29.6.1994.

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