Ivanhoe tables Oyu Tolgoi open pit reserves

Vancouver – Previous resource calculations on Ivanhoe Mines’ (IVN-T, IVN-N) planned open pit deposits at Oyu Tolgoi, in southern Mongolia, have been upgraded to the reserve category.

Proven and probable open pit reserves on the Southern Oyu deposits are estimated at 930 million tonnes grading 0.5% copper and 0.36 gram gold per tonne, or a 0.73% copper equivalent. Recoverable metals are pegged at about 8.9 billion pounds (over 4 million tonnes) of copper and 7.6 million oz. of gold.

The independent calculation by Australian engineering firm GRD Minproc assigned a block value net smelter return of US$9.05 per tonne for the reserves using metal prices of US$1.00 per pound for copper and US$400 per oz. for gold.

Ivanhoe continues development drilling on its Hugo Dummett deposits to upgrade inferred material to the measured and indicated category. A revised global resource estimate is anticipated soon and will include the Hugo North deposit and the Hugo North Extension on Ivanhoe’s joint venture with Entre Gold (ETG-V, EGI-X).

The re-tabulated resource calculation, by AMEC, on the Southern Oyu deposits resulted in a 1.12 billion tonne measured and indicated resource averaging 0.48% copper and 0.35 gram gold (0.7% copper equivalent). AMEC’s revised pit shells were calculated using a lower 0.3% copper equivalent cut-off grade and higher metal prices of US$1.15 per pound of copper and US$450 per oz. of gold. The revised estimate shows a 52% and 26% increase in contained copper and gold respectively over the mid-2005 resource calculation conducted using a 0.6% copper equivalent cut-off.

Last year’s estimates also identified 582 million tonnes of indicated resource in the deeper Hugo Dummett deposits grading 1.89% copper and 0.41 gram gold (2.15% copper equivalent) using the 0.6% copper equivalent cut-off. Further inferred resources of 1.07 billion tonnes of 1.07% copper and 0.21 gram gold (1.2% copper equivalent) were also shown.

As reviewed in its Integrated Development Plan tabled last Fall, Ivanhoe is planning development of Oyu Tolgoi with average annual output of more than one billion pounds (450,000 tonnes) of copper and 330,000 oz. of gold over a mine life of at least 35 years.