Osisko Mining Corporation
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Osisko Mining Corporation

July 29, 2005 08:00 ET

Osisko Reports New Extensions to Gold Mineralization at Malartic

MONTREAL, QUEBEC--(CCNMatthews - July 29, 2005) - Osisko Exploration Ltd. (TSX VENTURE:OSK)(Deutsche Boerse:EWX) is pleased to announce the results from the first three holes of the Phase Two drill program on its 100%-owned Canadian Malartic gold property, located in the Abitibi region of Quebec. The current program is testing grade and distribution of gold mineralization in the deposit to depths below those that were previously drilled (up to 300 meters depth) in order to confirm the potential for a large bulk-tonnage gold deposit. New results of the Phase Two program are very encouraging and are tabled below:



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Hole No. From (m) To (m) Length (m) Au g/t
CM05-666 58.0 116.8 58.8 1.07
CM05-667 111.5 188.5 77.0 0.70
CM05-668 154.5 301.5 147.0 1.02
CM05-669 41.2 310.7 269.5 1.04
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All holes were drilled vertically, south and east of the F zone. The results tabled above were calculated using a weighted average cut-off of 0.4 g/t Au over 20 meters. All holes, with the exception of CM05-666, intersected sediment-hosted mineralization followed by porphyry-hosted mineralization at depth. Details for each hole are as follows:

Hole CM05-666 tested an area above old mine workings at the southern limit of the F zone where mineralization had not been previously defined. This hole intersected 1.07 g/t Au over 58.8 meters in sediments and terminated in a stope. Mineralization is presumed to be continuous below the stope and further drilling is planned to test this area to a depth of 300 meters.

Hole CM05-667 tested the southern limit of the mineralized system, approximately 55 meters south of previously reported hole CM05-665 (1.00 g/t Au over 259 meters). This hole intersected, from a depth of 111.5 meters, 0.70 g/t Au over 77.0 meters in sediments followed by lower grade (0.25 g/t to 0.60 g/t Au) mineralization over 117 meters in porphyry.

Hole CM05-668 tested the mineralized system 60 meters further east than previous holes and intersected, from a depth of 154.5 meters, 1.02 g/t Au over 147.0 meters in sediments followed by highly silicified but barren porphyry over 30.3 meters.

Hole CM05-669 tested the mineralized system 82 meters further north than previous holes and intersected, from a depth of 41.2 meters, 1.56 g/t Au over 98.5 meters in sediments followed by 0.75 g/t Au over 171.0 meters in mixed sediment and porphyry. Mineralization in this hole is open at depth.

Drill data from the Osisko program has thus far confirmed continuity of low grade, bulk tonnage mineralization at the western end of the property over a 460 meters strike length. Management is very pleased with results obtained to date and now plans to drill-test the mineralized system at the eastern end of the property, about 730 meters east of CM05-668.

All reported assays were done by standard 50 g fire assaying-AA finish at ALS Chemex laboratories in Val d'Or, Quebec. Mr. Robert Wares, P. Geo. And President of Osisko, is the Qualified Person responsible for the preparation of this news release.

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