Overview

Mine Type	Open Pit
Stage	Permitting
Commodities	Gold Silver Copper
Mining Method	Truck & Shovel / Loader
Mine Life	...
Snapshot	Norte Abierto is one of the world's largest undeveloped gold and copper deposits, located in the Atacama Region of northern Chile. Approval of the environmental impact assessment for Cerro Casale was received in January 2013 from the Servicio de Evaluación Ambiental, the environmental authority of the Atacama region of Chile. Barrick and Newmont are evaluating ways in which the Norte Abierto deposits can be profitably developed by the joint venture.

Deposit type

• Porphyry
• Breccia pipe / Stockwork

Summary:

The Cerro Casale gold–copper deposit is located in the Aldebarán sub-district of the Maricunga Volcanic Belt in northern Chile. The Maricunga belt is made up of a series of coalescing composite, Miocene andesitic to rhyolitic volcanic centres that extend for 200 km along the western crest of the Andes. Reverse faults parallel to the axis of the Andes have uplifted hypabyssal intrusive rocks beneath the extrusive volcanics, exposing porphyry-hosted gold-copper deposits in the Aldebarán area. In addition to Cerro Casale, the Aldebarán property is host to several, less-explored, satellite deposits including Zona de Vetas, Eva, Cerro Roman, Estrella, Anfiteatro, Jotabeche, and Romancito Sur.

The Cerro Casale deposit is exposed in a hill of approximate 700 m of vertical relief and 1 km in diameter. Mineralization is related to a series of dacitic to dioritic intrusives, which were emplaced into Miocene andesites and volcaniclastic sedimentary rocks. The Miocene volcanic rocks overlie Oligocene conglomerates, which in turn, overlie Eocene basaltic andesites and rhyolite pyroclastic flows.

At Cerro Casale, gold–copper mineralization occurs in quartz–sulphide and quartz–magnetite–specularite veinlet stockworks developed in the dioritic to granodioritic intrusives and in adjacent volcanic wall rocks. Stockworks are most common in two dioritic intrusive phases, particularly where intrusive and hydrothermal breccias are developed. Mineralization has been encountered to at least 1,450 m vertically and 850 m along strike. The strike of mineralization follows west–northwest fault and fracture zones, and is open at depth along this strike. The main zone of mineralization pinches and swells from 250 m to 700 m along strike, and down dip steeply to the southwest. The highest grade mineralization is coincident with well-developed quartzsulphide stockworks in strongly potassic-altered intrusive rocks.

Oxidation resulting from weathering and/or high oxygen activity in the last phase of hydrothermal alteration overprints sulphide mineralization in the upper portion of the Cerro Casale deposit. Copper oxides are not common. Oxidation locally extends deeply along fault zones or within steeply-dipping breccia bodies.

Cerro Casale is considered to be an example of a gold–copper porphyry system based on the following:

- Hosted in a Mesozoic orogenic belt;

- Gold–copper mineralization at Cerro Casale formed during emplacement of multiple phases of diorite and granodiorite intrusions into a coeval sequence of intermediate to felsic volcanic rocks;

- Mineralization appears to be most closely related to strong potassic to phyllic alteration of the latest phases of intermediate to felsic intrusives and associated intrusive and hydrothermal breccias;

- Mineralization is focused in well-developed quartz–sulphide stockworks; veins, crackle and breccia zones are also present;

- Large tonnage but low grade.

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Comminution

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Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		May 23, 2024

Total Workforce	Year
......	2010