The Mining Segment of CAP S.A. conducts its operations through its subsidiary, Compañía Minera del Pacífico S.A. (CMP). For management purposes, CMP is organized into four main units, one of which is the Valle de Copiapó unit. This unit includes the operations of the Mina Cerro Negro Norte, Planta Magnetita, and the Puerto Punta Totoralillo.
CMP is a limited liability Company. It has two main shareholders, the controller with 74.9% of shares, CAP S.A. and MC Inversiones LTDA., subsidiary of Mitsubishi Corporation.
- subscription is required.
Summary:
The Cerro Negro Norte is iron oxide-apatite (IOA) deposit (Kiruna-type).
The Cerro Negro Norte IOA deposit is hosted in volcanic and volcanoclastic rocks of the Bandurrias Formation.
The Cerro Negro Norte host rocks are breccias and andesitic lavas that represent a roof pendant of volcanic rocks interspersed with granitoids. To the east, the Cerro Negro Norte deposit is limited by the Portezuelo Cucharas aplites and the La Borracha pluton.
The Cerro Negro Norte deposit comprises five magnetite ore zones from north to south: Cata Alfaro, Abanderada, Veta Central, Augusta, and Beduino. . Massive magnetite forms vertical to subvertical elongated bodies, tabular to lob-ular in shape, with a general NS orientation and distributed in an area of about 0.5× 5.0 km². The mineralization includes large amounts of magnetite locally altered to hematite (martitization), minor sulfides (pyrite +chalcopyrite), and local copper oxides.
The iron ore bodies consist of massive and disseminated magnetite with actinolite and minor apatite, pyrite, and chalcopyrite. According to their textural character-istics, the magnetite ore can be classified as massive, brecci-ated, stockwork, and disseminated. These bodies may exhibit abrupt contacts (e.g., eastern Abanderada) or gradational with respect to the host rock (e.g., western Abanderada, Veta Central). In addition, north of the Abanderada area, there are tabular magnetite bodies with NNE orientations that would indicate areas of weakness and fluid circulation (Raab 2001). Subhorizontal massive ore bodies a couple of meters thick, with variable extension and shape, show sharp contacts with the andesite rock in the Veta Central and Cata Alfaro areas (Vivallo et al. 1995a; Raab 2001).
These bodies are usually interstratified with volcanic rocks, a feature that has been interpreted as a complete replacement of andesitic lava flows by the magnetite (Raab 2001) or as intrusive or extru-sive bodies of magnetite (Vivallo et al. 1995a). Disseminated magnetite mineralization occurs mainly in the andesitic host rocks and, to a lesser extent, in diorite or monzodiorite-granodiorite dikes. Brecciated magnetite bodies are described to the east of Abanderada, north of Veta Central, and Cata Alfaro. In addition, magnetite clasts were observed in quartz-diorite igneous breccias that are spatially associated with monzodiorite and granodiorite dikes (Raab 2001).