LA-ICP-MS study of malachite from copper deposits in the Rosen ore field, Burgas ore district, SE Bulgaria

Archaeological findings of malachite ore pieces, and objects made of malachite or copper, raise the question of where the raw material was mined. Research in this direction is a challenge in modern applied mineralogy, especially concerning minerals from the oxidation zone of copper-bearing ores. According to recent studies in this field, a complex research method, including impurity elements, will provide a better distinction between different sources. The present paper is focused on the content of impurity elements in malachite ore samples from copper deposits in the Rosen ore field, SE Bulgaria, with mining activity in the past: Propadnala Voda, Sarneshko Kladenche, Meden Rid, Korucheshme, and Rosen. The nickel concentration obtained by LA-ICP-MS analyses is above 1000 ppm (1012.80–1505.15 ppm) in all studied samples, accompanied by the following element impurities: Zn, Co, Mg, As, Sb, Fe, Ag, Au, Sn, Se, and Te. The quantitative concentrations of Zn, Co, Mg, As, Ag, and Se vary in different ranges in the examined malachites from each locality. Based on this, it seems possible to differentiate between samples of each mineralization. These data would have to be supplemented by the analyses of more malachite ore samples from the region.