The Cortez gold mine is located 100 kilometres southwest of Elko, Nevada in Lander County. Cortez is wholly-owned by Barrick following the acquisition of the 40% joint venture interest (previously owned by Kennecott Explorations (Australia) Ltd., a subsidiary of Rio Tinto plc) in early 2008. The Pipeline property is 11 kilometres northwest and the Cortez Pediment property (which includes the Cortez Hills deposit) is 4 kilometres southeast of the original Cortez milling complex. The Pipeline and South Pipeline deposits are being mined by conventional open-pit methods.
Ore processing requires different methods depending upon the ore grade and metallurgical characteristics. At Cortez, three different metallurgical processes are employed for the recovery of gold. Lower-grade oxide ore is heap leached, while higher-grade non-refractory ore is treated in a conventional mill using cyanidation and a carbon-in-leach (“CIL”) process. Heap leached ore is hauled directly to leach pads for gold recovery. Carbonaceous mill ore is mined intermittently during the mining of the Pipeline/South Pipeline deposits. Refractory ore from Pipeline and the underground mine at Cortez Hills is treated through the autoclave and roaster at Goldstrike.
In 2008 Cortez’s production totaled 428,000 ounces of gold at total cash costs of $589 per ounce1. The Company’s proven and probable mineral reserves as of December 31, 2008 are estimated at 13.4 million ounces of gold2.
Cortez Hills
Cortez Hills is about 100 kilometres from Goldstrike in Nevada on the Cortez property, which covers approximately 2,800 square kilometres on one of the world’s most highly prospective mineral trends. Located next to the existing Cortez Pipeline mine on the Battle Mountain trend, Cortez Hills is expected to be a significant contributor to Barrick as a key, long life, low cost mine. Total construction costs remain in line with the pre-production capital budget of about U$500 million. The project is on schedule to produce first gold in Q1 2010. Once in production, Cortez’s (including Pipeline) average annual production is expected to be about 1 million ounces of gold for the first full five years3.The Cortez Hills open pit mine will be mined by conventional methods; oxide ore from the mine will be conveyed across the valley to be processed at existing facilities.
The Cortez Hills underground is accessed by twin declines portaled in the old Cortez Gold F canyon pit. Mining of the breccia ore zone will be done using underhand cut and fill mining methods with cemented rock fill as backfill. The top cut of the underground mine will eventually be the bottom bench of the Cortez Hills open pit.
The Cortez property has significant exploration potential from which Barrick believes further value can be unlocked. For 2009, an aggressive work program is scheduled as a follow up to the exploration success Barrick had in 20084.
1 Click here for more information regarding the calculation of total cash costs. 2 Click here for more information regarding reserve and resource measurements.
3 Assuming satisfactory resolution of pending litigation. Click here for more information.
4 Click here for more information on exploration.