Introduction
Porphyry ore deposits are some of the major resources for minerals such as copper. Porphyry copper deposits can be classified as economic copper ore bodies that form from hydrothermal fluids. The fluids originate from a magma chamber several kilometers below the porphyry deposit. Other minerals, such as gold, silver and molybdenite, can be associated with copper …show more content…
These molecules include SO4 2- , H2S and HS- and are important during complexing among S-H-O containing species (Bowen and Gunatilaka, 1977). The optimal pH range for transport is considered to be between pH 6 and 8 with temperatures around 300̊ C (Bowen and Gunatilaka, 1977). H2S and HS- are important for transport of sulfide ores at lower temperatures. In higher temperature deposits, around 500̊ C, S2- is the predominant species. (Bowen and Gunatilaka, 1977). Mixing of ore solutions with meteoric waters results in oxidation with the release of H+ ions that decreases pH and the transportation of cooled/diluted solution (Bowen and Gunatilaka, 1977).
Alkali chlorides are abundant in copper ore solution. The ore fluids are high in Cl, Na, and Ca (Bowen and Gunatilaka, 1977). The two principal copper reactions are: Cu2+ + 3CL-↔CuCl3- and Cu+ + 3CL-↔CuCl32-. The copper content, or grade of an ore body, is directly related to temperature and Cl content (Bowen and Gunatilaka,