Osisko Mining Corporation
TSX : OSK
FRANKFURT : EWX

Osisko Mining Corporation

March 18, 2008 08:15 ET

Osisko Intersects 107m Averaging 1.47 G/T Au at Depth in Norrie Zone

New Gold Zone Shows System Still Open 2.5 km East of Main Deposit

MONTREAL, QUEBEC--(Marketwire - March 18, 2008) - Osisko Exploration Ltd. (TSX:OSK)(FRANKFURT:EWX) and Golden Valley Mines Ltd.(GZZ:TSX VENTURE:GZZ) are pleased to announce results from a subvertical exploration hole that tested the Norrie Zone, a deep, distinct mineralized target located approximately 2.5 kilometres east of the center of the main Canadian Malartic deposit. The Norrie Zone straddles the boundary between the Malartic CHL property, currently under option by Osisko, and Osisko's 100%-owned Canadian Malartic property. The hole was designed to test the vertical extent of this mineralized system and has intersected significant widths of disseminated gold mineralization in three separate zones. Within the target zone, drill hole CHL07-2000 cut 107 metres averaging 1.47 g/t Au between 1483 m and 1590 m down hole depth. Results from the new hole are tabled below:




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Hole No. Easting From (m) To (m) Length (m) Au g/t
CHL07-2000 6530E 91.2 97.0 5.8 6.30
And 432.5 457.8 25.3 0.50
And 630.5 936.0 305.5 0.31
And 1483.0 1590.0 107.0 1.47
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The Norrie Zone was initially identified through compilation of historical data from the East Malartic mine. A series of five underground horizontal holes, drilled in the late 1960's and collared from the 31st level of the mine at a depth of 1485 metres intersected disseminated mineralization in Pontiac metasediments. Examination of historical core by Osisko indicated that the mineralization is similar to that at the Canadian Malartic deposit, which has been confirmed with DDH CM07-2000. Historical results from the horizontal holes are summarized in the table below (previously reported in a press release dated June 20, 2007) :



HISTORICAL HORIZONTAL DRILLING - NORRIE ZONE
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Hole No. Section From (m) To (m) Length (m) Au g/t
UM31-01 6786E 0.0 120.7 120.7 1.86
UM31-42 6588E 0.0 234.7 234.7 1.41
UM31-52 6528E 0.0 236.2 236.2 1.71
UM31-54 6466E 0.0 260.6 260.6 1.32
UM31-58 6405E 48.8 128.0 79.2 0.89
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The historical drilling indicates a mineralized zone measuring at least 380 metres long, up to 260 metres wide, and the new drill hole indicates the zone is approximately 100 m thick.

The deep intersections are significant in that they confirm the presence of a very large system of Canadian Malartic-style disseminated gold mineralization in Pontiac metasediments, including anomalous gold values over very long vertical extents (0.31 g/t Au over 305 m) above the Norrie zone. The alteration halo and gold-bearing system, including the Canadian Malartic deposit, are now known to be at least 3.5 km long, up to 1 km wide and reaching depths of 1.5 km. Further exploration work is planned to establish if the Norrie zone comes to surface further to the south, and to evaluate the remaining 3 km strike length of Pontiac metasediments to the east of CM07-2000, south of the Cadillac fault and particularly along the footwall of the East Malartic Mine workings.

Sean Roosen, President and CEO of Osisko, commented: "We are very excited with the confirmation of the Norrie Zone. Testing this target has shown that the Canadian Malartic geological model is working very well and that the mineralized system continues to the east, showing impressive dimensions that are the hallmarks of a world-class gold bearing system. While the Norrie Zone has yet to be proven to have economic grades at these depths, it opens the potential for higher-grade gold zones which may be amenable to underground block-caving mining methods. Exploration work within the large 4.5 km-long target east of the Canadian Malartic deposit will continue in order to investigate the potential for additional economic gold mineralization south of the Cadillac fault, in the previously unexplored Pontiac metasediments." All NQ core assays reported above were obtained by standard 50 g fire assaying-AA finish at ALS Chemex laboratories in Val d'Or, Quebec. Reported weighted averages were calculated using a minimum of 0.30 g/t Au over successive maximum intervals of 20 metres with no upper cut-off of individual assays.

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 $180 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.

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
    Osisko Exploration Ltd.
    Daniel Boase
    Investor Relations
    416-742-5600
    Toll free: 1-866-580-8891