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Chile - El Toqui
The El Toqui mine is located in Chile 's Region XI, approximately 1,350 kilometres south of Santiago and 120 kilometres northeast of Coyhaique ( view map).
The El Toqui deposit was discovered in the early 1970's. Metallgesellschaft AG owned the property for a number of years and then sold it to a Chilean entrepreneur.
The property was subsequently purchased by Lac Minerals. In 1994, Barrick Gold Corporation acquired Lac Minerals which included El Toqui. Breakwater purchased El Toqui in August 1997.
The El Toqui property includes the Doña Rosa zinc/gold mine and the San Antonio and Mallin-Monica zinc/lead mines, the Estatuas mine and the Concordia deposit. Processing is carried out through a 1,500 tonne per day concentrating plant.
Zinc/gold mineralization at El Toqui occurs as manto deposits hosted by an 8 metre to 12 metre thick bed of fossiliferous limestone, known as the Main Manto unit. The El Toqui deposits all dip gently to the south, and are amenable to room and pillar mining, with 11 metre rooms around 8 metre pillars. The Doña Rosa Mine is accessed via an adit.
Summary of Mineral Reserves and Resources
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31 December, 2007 |
31 December, 2006 |
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Tonnes
(000s) |
Zn
(%) |
Pb
(%) |
Cu
(%) |
Ag
g/t |
Au
g/t |
Tonnes
(000s) |
Zn
(%) |
Pb
(%) |
Cu
(%) |
Ag
g/t |
Au
g/t |
|
Proven and Probable Reserves |
4,715 |
7.3 |
0.5 |
0.1 |
11 |
1.1 |
2,869 |
8.2 |
- |
- |
- |
1.3 |
|
Measured and Indicated Resources |
5,346 |
8.1 |
0.5 |
0.1 |
13 |
1.3 |
3,597 |
8.9 |
- |
- |
- |
1.3 |
|
Inferred Resources |
4,761 |
7.1 |
0.5 |
0.1 |
15 |
0.6 |
4,626 |
8.5 |
- |
- |
- |
0.5 |
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Measured and Indicated Resources include Proven and Probable Reserves. |
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For the December 31, 2007 mineral reserve estimates, metal prices, including premiums, used to determine economic viability were US$1.12/lb. zinc, C$/US$ exchange rate of 1.09, US$600/oz. gold, US$12.00/oz. silver, US$2.55/lb. copper and US$0.54/lb. lead. For Grevet B, the satellite deposit at Langlois, the metal prices used were US$1.45/lb. zinc, C$/US$ exchange rate of 1.09, US$12.00/oz. silver and US$3.27/lb. copper. Higher prices were used on this deposit as it is expected that it will be mined over the next two years.
The concentrator utilizes conventional crushing and grinding and differential flotation including rougher and cleaner flotation circuits which produce gold and zinc concentrates. The concentrates are separately thickened and filtered on vacuum and pressure filters. The concentrates are trucked to Puerto Chacabucco where they are loaded onto ships for transport to smelters around the world.
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2007 |
2006 |
2005 |
Ore Milled (Tonnes)
Zinc (%)
Gold (g/t) |
522,082
6.9
2.7
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539,803
6.5
2.4 |
519,963
6.0
2.9 |
Concentrate Production
Zinc (tonnes)
Recovery (%)
Grade (%)
Gold (tonnes)
Recovery (%)
Grade (g/t) |
65,322
90.0
49.9
6,251
51.4
120.1
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63,617
91.0
49.9
4,237
68.5
192.1
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56,552
90.4
50.1
4,110
51.4
221.7
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Metal in Concentrates
Zinc (tonnes)
Gold (ounces)
Silver (ounces)
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32,191
37,021
155,890
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31,725
36,795
71,703
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28,347
41,605
131,020
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