- journal_title：The Canadian Mineralogist
- Contributor：Carlos Palacios ; Gérard Hérail ; Brian Townley ; Víctor Maksaev ; Fabián Sepúlveda ; Philippe de Parseval ; Pablo Rivas ; Alfredo Lahsen ; Miguel Angel Parada
- Publisher：Mineralogical Association of Canada
- Date：2001-
- Format：text/html
- Language：en
- Identifier：10.2113/gscanmin.39.3.907
- journal_abbrev：Can Mineral
- issn：0008-4476
- volume：39
- issue：3
- firstpage：907
- section：Articles
The Cerro Casale gold-rich orebody, located in the Maricunga Belt, in northern Chile, is a Miocene deposit hosted in diorite and granodiorite porphyries. Two broad types of hypogene alteration are associated with gold mineralization: potassic and white mica. The geochemical study of gold crystals involved the electron-microprobe analysis of 176 gold grains from 29 samples. These samples were collected from diamond drill-cores at various depths. The gold crystals deposited during potassic alteration have high abundances of Ag (8 to 28 wt.%) and low concentrations of Cu (n.d. to 0.24 wt.%). However, gold crystals deposited during white mica alteration have low concentrations of Ag (1 to 9 wt.%) and higher abundances of Cu (0.06 to 0.34 wt.%). In addition, gold crystals recovered from fragments of both porphyries included in a white mica hydrothermal breccia apparently maintain their original Ag and Cu concentrations.