Goldstrike Mine Property | gold mine

 mine, gold mine

The Goldstrike Property (Complex) is located on the Carlin Trend and is owned and operated by Barrick Gold, who acquired it from the Western States-Pancana joint venture for a total cost of $62 million. The operation includes open pit and underground mining on the Betze, Post, Screamer, Meikle, and several other small deposits. The image attached shows the surface ownership only, not the mineral ownership as Newmont Corporation owned and mined Deep Post which is located at the SE end of the Post Deposit. The approximate gold endowment for each deposit is shown below in millions of ounces:

-Betze: 29
-Post: 3.5
-Screamer: 5
-Meikle: 7
-Rodeo: 4
-Others1: 0.4
-Others2: 1.4
-Others3: 0.1

(Others1 includes: Long Lac, Winston, Bazza Deposits, Shalosky, Skarn Hill)
(Others2 includes: Griffin, West Griffin, Barrel, Banshee)
(Others3 includes: Goldstrike Stock, Number 9)

The Betze-Post pit is a truck-and-shovel operation using large electric shovels. Meikle is a high-grade ore body which is mined by transverse longhole stoping, underhand drift and fill mining methods. Rodeo is a further extension of the mineralization found at Goldstrike and is a trackless operation, using two different underground mining methods: long-hole open stoping and drift-and-fill. The Goldstrike Property consists of two processing facilities: (1) an autoclave circuit, which is used to treat the property’s non-carbonaceous sulfide (refractory) ore; and (2) the roaster, used for treating carbonaceous ore (not suitable for autoclaving). These facilities treat ores from both the surface and underground operations.

In 2011, the Goldstrike Property produced 1.09 million ounces of gold at total cash costs of $511 per ounce1. Production in 2012 is expected to be 1.25-1.30 million ounces as the open pit moves back into a higher ore phase. 2012 total cash costs are expected to be $525-$575 per ounce. Goldstrike’s proven and probable mineral reserves as of December 31, 2011 was 12.4 million ounces of gold.

Goldstrike’s open pit mine is an open pit truck-and-shovel operation, using standard, proven equipment. Two different underground mining methods are used at the underground mine, long-hole open stoping and drift-and-fill (used for flat-lying mineralization or where ground conditions are less competent). The underground mine is a trackless operation. Goldstrike’s production in total was 1,239 thousand ounces of gold in 2010 at cash costs of $530 per ounce compared to 1,419 thousand ounces of gold in 2009 at cash costs of $464 per ounce. Based on existing reserves and production capacity, the expected remaining mine life is 12 years for underground mining, 15 years for open pit mining and 15 years for processing operations. The reduction in the expected remaining life of processing operations to 15 years (2009: 26 years) is mainly a result of the extension of the operating life of the autoclaves. The extension of the operating life of the autoclaves is due to the conversion of the pressure oxidation process from an acid circuit to an alkaline circuit and the introduction of thiosulfate processing, both of which are further described below. By extending the operating life of the autoclaves, Goldstrike will be able to process certain ore at an earlier stage using the autoclaves instead of processing that same ore at later stage using the roaster.



The underground mine includes two major orebodies: Meikle and Rodeo. The Meikle orebody, located 1.6 kilometers north of the open pit mine, is a high grade orebody which was discovered in 1989 and started production in 1996. The Meikle orebody incorporates 5 mineralized zones: the Main Meikle, Meikle Extension, South Meikle, Griffin, and West Griffin. The Rodeo orebody, located 0.5 kilometers northwest of the open pit mine, is a moderate grade orebody discovered in 1988 and brought into production in 2002. The Rodeo orebody includes four mineralized zones: Upper Rodeo, Lower Rodeo, West Rodeo, and Barrel. The Meikle and Rodeo orebodies are interconnected by two haulage drifts and can be accessed from two shafts and by a decline at the bottom of the open pit mine.

The property has two processing facilities: an autoclave installation, which is used to treat the property’s non-carbonaceous sulphide (refractory) ore; and the roaster, which is used to treat the property’s carbonaceous ore (whose active carbon content responds poorly to autoclaving). The combined capacity of these two facilities is approximately 33,000 to 35,000 tons per day. These process facilities treat the ore from Goldstrike’s open pit and underground mines. Gold contained in recovered ore is processed into doré on-site and shipped to outside refineries for processing into gold bullion.


Reference:

www.nbmg.unr.edu/dox/b111/goldstrike.pdf

www.sec.gov/Archives/edgar/data/756894/0001193125121376...

www.barrick.com/GlobalOperations/NorthAmerica/Goldstrik...