Algamarca mine, Cachachi District, Cajabamba Province, Cajamarca, Perui

Regional Level Types
Algamarca mine	Mine
Cachachi District	District
Cajabamba Province	Province
Cajamarca	Region
Peru	Country

Minera Algamarca explored the area and developed 5 adits at the Algamarca mine.

Most of the Cu-Ag-(Au) vein deposits exploited by Algamarca were on the southwestern limb of the Algamarca anticline.

Sulliden Gold Corporation acquired the mine and exploration are in 2002.

The mine is now part of the Shahuindo Project.

It consists of veins trending perpendicularly or obliquely to the anticline axis. Stratigraphically, the Algamarca anticline is composed by the late Jurassic black shales with intercalations of fine-grained sandstone of the Chicama Formation and the overlying lower Cretaceous fluvio-deltaic and shallow-marine sequences of the Goyllarisquizga Group. The Goyllarisquizga Group includes, from bottom to top, quartz-rich massive sandstone with minor intercalations of shale, siltstone and coal bed of the Chimú Formation, black shales with lenticular siltstones, minor mudstones and limestones of the Santa Formation, interbedded siltstone, mudstone, and sandstone of the Carhuaz Formation, and quartz-rich sandstone with minor interbedded siltstone of the Farrat Formation. Sandstones from the Chimú, Carhuaz, and Farrat formations are the main country rocks for the epithermal mineralization in the district including the Algamarca deposit. Oligocene-Miocene andesitic and dacitic intrusive stocks were emplaced at the intersection of NW-SE thrust faults and later NE-SW transverse faults, or along the axis of the Algamarca anticline. They outcrop in the area and were intercepted by underground workings of the Algamarca mine. The Algamarca deposit has been exploited since Spanish colonial times. Later, Minera Algamarca SA operated an underground mine between 1945 and 1989. Some veins are currently mined on a small scale by AMASBA artisanal miners’ association.
The Algamarca deposit is composed by seven veins labelled as Descubridora, San Blas, Los Alisos, Rosario, Lucy, Concepción, and Choloque, all of them of thicknesses varying from 0.1 to 2 m, up to more than 600 m in length, and extending over about 200 m in the vertical direction. Grades of up to 14 g/t Au, 2700 g/t Ag, and 25 wt% Cu were reported from one-sampling analyses in the Descubridora vein (the most exploited at Algamarca), which is hosted by quartz-rich sandstones of the Chimú Formation.
The deposit was classified as intermediate-sulfidation epithermal based on sulfide and gangue mineral assemblages. Includes gold and silver tellurides.

Other Regions, Features and Areas containing this locality

References