The El Jardín mine belongs to a belt of stratabound Cu, Ag-Cu and Ag deposits in the lower part of the Hornitos Formation (Upper Cretaceous?, Paleocene?) in northern Chile. Other examples of this belt are: Elisa de Bordos [Ag-(Hg); see Jurgeit and Fontboté this Vol.], Amolanas (Cu-Ag), El Venado (Ag-Cu), Boli-viana [Ag-(Hg)], Altar de Cobre (Cu) and a great number of smaller deposits (Fig. 1). Exhibiting differences in ore textures, the deposits show similarities in host rock lithology, and mineralogic and geochemical composition. Vein-type deposits occur in the same stratigraphic position. Nordenskjöld (1897), Kuntz (1923), Little (1926), Cortés (1942), and Segerstrom (1959) provided early descriptions followed by Lortie and Clark (1974, 1987), Mayer and Fontboté (1984, 1986), Jurgeit et al. (1986) and Mayer (1988). This paper is based on field and laboratory work and presents a short description of host rock lithology, diagenetic evolution, ore geometry, composition, and zonation of the El Jardín mine (27°45′30″S/70°11′30″W), 47 km SEE of Copiapó, capital of the Atacama Province, N-Chile (Fig. 1). The main ore horizon is mined in several smaller mines at a length of about 3 km. A second ore horizon, stratigraphically 40 m above the main orebody, was mined during 1982 and 1983, but the production ceased due to processing problems. The production is about 100 t/day with an ore grade of 1.8% Cu and 100 g/t Ag. The present description is restricted to the main orebody in the sectors Zulema, San Pedro and San Antonio (Fig. 3).
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- The Stratiform Ag-Cu Deposit El Jardín, Northern Chile
C. K. Mayer
- Springer Berlin Heidelberg