Secondary Products of Arsenopyrite in the Terrubias Mining Area (Salamanca, Spain)

Abstract

Oxidation of arsenopyrite can result in the mobilisation and migration of As into the environment. This study considers the arsenopyrite-rich mine wastes that have undergone more than three decades of oxidation in the Terrubias mining area. In this area two Sn-W mineralization types are present: stratiform with calcosilicate bands, and in subvertical veins of NNE-NE and N100-130E directions, cutting the scheelite-rich calcosilicate bands. The paragenesis of these veins is dominated by quartz, mica, turmaline, wolframite, scheelite, casiterite and arsenopyrite. The aim of this work is to identify the arsenopyrite oxidation products in the Terrubias mining area in order to evaluate if arsenic is fixed by them or, on the contrary, is easily released, with the consequent risk of contamination of surrounding ecosystem compartments.