Osisko Mining Corporation

• History

  The Canadian Malartic deposit was discovered in 1926. Underground development began in 1928 following a 26 hole surface drill program and production started in 1935. The mine closed in 1965 after producing 1,080,000 ounces of gold from 9.93 million tones of ore grading 3 to 6 g/t Au. Gold is finely disseminated and occurs in the native state, and was recovered in a mill by standard cyanide leaching (90% average recovery over the mine life). Following closure of the mine, the property remained idle until purchased by Lac Minerals in 1979.

  From 1980 to 1988, Lac Minerals explored the property with the objective of defining a near-surface (< 100 metres deep) economic deposit amenable to open pit mining. The exploration program led to the definition of 5 near-surface gold zones forming an aggregate historical resource (pre 43-101) of approximately 8,160,000 metric tonnes @ 1.98 grams/tonne Au (520,000 oz Au)1

  WOLFE ZONE	3,929,250 tonnes @ 2.00 g/t Au	(252,510 ounces Au)
  F ZONE	2,039,018 tonnes @ 1.78 g/t Au	(116,875 ounces Au)
  P ZONE	826,933 tonnes @ 1.78 g/t Au	( 47,400 ounces Au)
  GILBERT ZONE	863,046 tonnes @ 2.33 g/t Au	( 64,690 ounces Au)
  A ZONE	503,289 tonnes @ 2.43 g/t Au	( 39,390 ounces Au)
  TOTAL	8,161,536 tonnes @ 1.98 grams/tonne Au	(520,865 oz Au)¹

  Metallurgical tests carried out by Lac Minerals indicated a non-refractory ore with recoveries of 86%-90% on a standard cyanide leach circuit (exclusive of CIP).

  The project was shelved when Barrick Gold Corp. acquired Lac Minerals in the early nineties. Barrick Gold sold the property to McWatters Mining in 2003. McWatters went bankrupt in 2004, and in late 2004, Osisko purchased a 100% interest in the property (initially 6 claims and one mining concession) through the McWatters liquidating trustee. A 2 to 3 % sliding scale net smelter royalty is payable to Barrick, half of which can be purchased back by the Company for $1,500,000 CDN. Since the initial acquisition, Osisko has successfully acquired additional claims and the property now comprises 104 claims and one mining concession with a total surface area of 4442 hectares (10,976 acres).

  A 3000-tpd mill with modern cyanide and floatation circuits (East Malartic mill) is located immediately east of the property, which was last operated in 2002 to treat ore from the Barrick's Bousquet Mine. The inactive mill is now the property of the Quebec government. Richmont's Camflo mill is located 12 km to the east along highway 117.

  1 - Osisko Exploration Ltd. has not verified the classification of these resources under National Instrument 43-101 and therefore the above-quoted figures are reported as unclassified historical resource estimates. Resource estimates prepared under reporting codes other than National Instrument 43-101 should not be relied upon to conform to current standards and definitions. Osisko believes, however, that the resource estimates reported by Lac Minerals are relevant and reliable.

Canadian Malartic Maps »