Osisko Mining Corporation
TSX : OSK
FRANKFURT : EWX

Osisko Mining Corporation

October 26, 2007 16:37 ET

Osisko Outlines New Gold Zone on Golden Valley's CHL Property

New Mineralization in Jeffrey Zone located 3.6 km from Canadian Malartic Deposit

MONTREAL, QUEBEC--(Marketwire - Oct. 26, 2007) - Osisko Exploration Ltd. (TSX VENTURE:OSK)(FRANKFURT:EWX) is pleased to announce that ongoing compilation on the Malartic CHL property, currently under option from Golden Valley Mines Ltd. (GZZ:TSX-V), has outlined a new porphyry-hosted gold mineralized zone (the "Jeffrey Zone"), located approximately 3.6 kilometres east of the center of the Canadian Malartic deposit and 2.1 kilometers east of recently announced drill hole CM07-2008 (see October 23, 2008 press release).

Compilation of historical drilling performed by East Malartic Mines in the 1930's and by Lac Minerals in the 1980's has outlined a zone of disseminated mineralization hosted within the CHL Porphyry intrusion where it comes into contact with the southern edge of the Cadillac fault. Notable historical intersections include:



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Hole No. From (m) To (m) Length (m) Au g/t
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EMS-106 139.3 200.4 61.1 0.57
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EMS-107 118.2 196.9 78.7 0.62
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EMS-110 170.8 205.6 34.8 1.00
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G82-01 69.6 94.8 25.2 1.63
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G82-02 13.7 88.4 74.7 1.30
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G82-03 91.1 169.1 78.0 1.33
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G82-05 143.3 216.4 73.1 0.83
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The east-west oriented Jeffrey Zone appears to extend over a distance of 800 meters and have a true thickness from 20 to 60 metres. Several of the historical holes stopped in disseminated mineralization and the system is open to depth beyond 150 meters. The porphyry body, as well as surrounding peripheral dykes that are hosted in volcanic rocks, contain higher-grade shear-hosted vein mineralization at deeper levels, including the following intersections (true widths unknown): 1.5 metres averaging 28.0 g/t Au (DDH EMS-240 from 127.0 to 128.5 metres); 14.0 metres averaging 10.2 g/t Au (DDH EM88-17 from 863.2 to 875.4 metres) and 4.1 metres averaging 9.0 g/t Au (DDH G83-07 from 179.6 to 183.7 metres).

Osisko also wishes to announce that grab samples collected from a waste dump of material derived from the main porphyry intrusion at the past-producing Amphi Mine yielded geologically significant results. The Amphi Mine is located 2.0 kilometres northwest of the center of the Canadian Malartic deposit and the porphyry intrusion formed the footwall of the mined-out ore body. Field observations made in the waste dumps and in the abandoned Amphi open pit indicate that the porphyritic material includes stockworks comprising at least four generations of mineralized, cross-cutting quartz-pyrite veins. One hundred and twenty-five (125) grab samples collected from the surface of the dumps yielded an average grade of 1.15 g/t Au, including 14 samples containing vein material that assayed up to 39.0 g/t Au. Porphyritic material free of veins produced values ranging from less than0.005 to 1.70 g/t Au. Although the results from the grab samples are not statistically significant, they nevertheless indicate potential for near-surface, low grade bulk tonnage mineralization within the Amphi porphyry intrusion. The Amphi porphyry extends for approximately 1.1 kilometers in a northwest direction, it is 50 to 110 metres thick and extends to a minimum depth of 200 metres.

The Jeffrey Zone and the Amphi Porphyry both constitute new, highly favorable exploration targets for low-grade, bulk tonnage mineralization in the Malartic camp. Osisko plans to drill-test these targets in Q1 2008 (total of 2,000 m of drilling on each target). As previously announced, other targets that will be drilled before year end include the Southeastern Extension of the Canadian Malartic deposit as well as the Western Porphyry Zone.

Osisko Exploration Ltd. is currently evaluating the Canadian Malartic gold deposit and adjacent areas for a large-scale open pit, bulk-tonnage mining operation. The Company is well-funded with approximately $80 million on hand and is carrying out an aggressive definition drilling and exploration campaign. An updated NI 43-101 compliant, inferred gold resource estimate on the main Canadian Malartic deposit was released on July 5, 2007 and the full report is available on SEDAR.

All grab sample assays reported above were obtained by standard 30 g fire assaying-AA finish at ALS Chemex laboratories in Val d'Or, Quebec. Mr. Robert Wares, P. Geo. and Executive Vice-President of Osisko, is the Qualified Person responsible for the technical information reported in this news release.

Contact Information

  • Osisko Exploration Ltd.
    John Burzynski
    Vice-President Corporate Development
    514-735-7131
    www.osisko.com
    or
    Daniel Boase
    Investor Relations
    416-742-5600
    Toll Free: 1-866-580-8891