First cathode at Quebrada Blanca

The Quebrada Blanca mine in northern Chile has yielded its first cathode copper.

Perched in the Andes at an altitude of 4,300 metres, near the Bolivian border, the mine is in the midst of completing its startup phase. And Cominco (TSE), which holds a 38.25% participating interest, reports that the project is on target to produce 75,000 tonnes of high-grade cathode copper annually using bacterial heap leaching and solvent extraction-electrowinning. A minelife of 14 years is projected, based on an 89-million-tonne secondary sulphide orebody grading 1.3% copper. An underlying primary zone of higher tonnage and lower grade would then be exposed, which could add to the minelife, provided additional capital expenditures are made. Teck (TSE) has a 29.25% interest, while Cominco Resources International (TSE) holds a 9% carried interest. The remainder is held by Chilean companies. The three companies are also participating equally in a joint venture to explore and acquire other Chilean projects. Promising results were reported from recent drilling on the Celeste property, 40 km northeast of Chanaral in northern Chile.

A hole in the North zone (drilled westerly at an inclination of 70) cut 0.9% copper over 114 metres, which includes 2.8% over 21 metres. A second hole — 100 metres east of the first — intersected the same zone and returned 1.1% over 73 metres, including 2% over 28 metres. The partners noted that the zone could be thicker than indicated, as the drill hole was prematurely terminated in the mineralization owing to a technical drilling problem. Cominco Resources reports that the North zone dips relatively shallowly to the east and has not been closed off downdip. Encouraging results were obtained from other drilling (also to the west and inclined at 70). These holes returned 1% copper over 21 metres, 0.4% over 82 metres in an upper section and 1.1% over 11 metres in a lower section, as well as 0.7% over 40 metres.

A reverse-circulation drill hole intersected 1% copper over 86 metres in the South zone, situated 7 km from the North zone, which includes 1.5% over 40 metres. Another hole, 400 metres along strike to the south, cut 3% copper and 0.8 grams gold per tonne over 11 metres.

Most of the copper occurs as sulphides, although some copper oxides were noted to occur near surface.

The 225-sq.-km. Celeste property is about 1,000 metres above sea level, near an electrical power source, and features road access to the port of Chanaral. A program is under way to confirm the presence of water on the joint venture-held concession.