Osisko Mining Corporation
TSX : OSK
FRANKFURT : EWX

Osisko Mining Corporation

September 18, 2008 09:52 ET

Osisko Intersects 258 Metres Averaging 2.13 g/t Gold at Barnat

MONTREAL, QUEBEC--(Marketwire - Sept. 18, 2008) - Osisko Mining Corporation ("Osisko") (TSX:OSK)(FRANKFURT:EWX) is pleased to announce new results from the definition drill program currently under way at South Barnat, a separate gold mineralized zone located approximately 1200 metres northeast of the center of the Canadian Malartic deposit. Significant results include 3.22 g/t Au over 83.5 metres (BA08-3039) and 2.13 g/t Au over 258.5 metres (BA08-3061). Higher grade intercepts include 12.49 g/t Au over 4.0 metres (BA08-3048) and 10.43 g/t Au over 4.9 metres in hole BA08-3049. Results from twenty-two new holes are tabled below:



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Hole No. Section From (m) To (m) Length (m) Au g/t

BA08-3035 300E 134.6 146.5 11.9 2.30
And 212.7 256.6 43.9 1.78
including 212.7 214.0 1.3 18.05
BA08-3036 250E 141.3 165.0 23.7 1.75
And 183.0 222.0 39.0 2.26
And 293.0 300.0 7.0 6.61
BA08-3039 550E 37.5 121.0 83.5 3.22
including 61.5 63.0 1.5 44.90
And 149.5 186.5 37.0 0.98
And 214.0 296.5 82.5 0.76
BA08-3043 150E 251.0 335.7 84.7 1.01
BA08-3045 500E 297.5 317.0 19.5 2.45
BA08-3046 500E 119.5 145.0 25.5 1.96
BA08-3047 550E 89.9 108.5 18.6 1.41
BA08-3048 550E 41.0 70.5 29.5 0.99
And 100.0 144.0 44.0 2.93
including 135.5 139.5 4.0 12.49
BA08-3049 550E 30.1 35.0 4.9 10.43
And 93.5 108.0 14.5 1.93
BA08-3051 100E 73.5 131.5 58.0 2.69
including 79.5 81.0 1.5 43.70
BA08-3052 050E 96.4 107.9 11.5 4.57
And 251.5 271.0 19.5 1.14
BA08-3053 050E 94.0 129.5 35.5 0.57
BA08-3054 450E 63.8 79.2 15.4 3.05
And 177.0 246.6 77.6 1.96
including 177.0 177.9 0.9 55.60
BA08-3055 450E 65.0 110.5 45.5 1.42
And 274.0 280.3 6.3 2.91
BA08-3056 500E 83.9 145.5 61.6 1.73
And 186.6 197.5 10.9 3.49
BA08-3057 500E 22.0 44.5 22.5 1.45
BA08-3058 100E 17.5 51.5 34.00 2.81
And 149.0 164.0 15.0 3.74
BA08-3059 050E 20.0 56.5 36.5 1.37
BA08-3060 000E 31.0 50.0 19.0 1.50
And 122.5 141.5 19.0 1.03
BA08-3061 700E 141.0 399.5 258.5 2.13
including 190.5 193.0 2.5 15.90
including 378.7 379.7 1.0 19.75
BA08-3062 100E 93.0 158.5 65.5 0.73
BA08-3063 100E 65.5 118.0 52.5 2.01
including 98.0 99.0 1.0 22.40
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Drill hole BA08-3041 was lost in a fault gouge. Drill holes BA08-3044 and BA08-3050 penetrated historic mine workings and did not intersect significant mineralization. Drill holes BA08-3046 and BA08-3048 intercepted historic mine workings and did not reach the intended target depths. Drill hole BA08-3061 was a steeply inclined hole (83 degrees) designed to test the vertical extent of the mineralized system on section 700E. Assays for drill hole BA08-3061 between 0 and 103 metres are pending. Assay results from further holes at South Barnat are also pending.

The definition drill program is focused on an 850 metre-long grid oriented northwest-southeast with drill sections spaced 50 metres apart. All holes on this grid are inclined 45 to 75 degrees to the northeast or southwest. True widths of the mineralized intersections reported above are 40 to 70 percent of the drilled intersections.

Drilling to date suggests that the minimum strike length of the South Barnat Zone is 850 metres with a true width between 20 and 160 metres. The mineralized zone is open along strike to the southeast, where it merges with the old East Malartic Mine. It extends to a minimum depth of 250 metres in the southeastern portion, where the system is still open at depth. Drill hole BA08-3061 suggests the system may extend as deep as 400 metres below surface. Estimated depth in the northwestern third of the deposit is 130 to 200 metres.

Mineralization in the South Barnat Zone is located to the north and south of the old Barnat and East Malartic mine workings, largely along the southern edge of the Cadillac fault. The gold mineralization comprises multiple subvertical, tabular subzones hosted both in silicified greywackes of the Pontiac Group south of the fault contact and in schistose, carbonated and biotitic ultramafic rocks north of the fault contact. Porphyry dykes on both sides of the fault contain disseminated mineralization as well as late quartz veins containing visible gold. Gold mineralization in the South Barnat Zone likely extends to the east along the north and south walls of the past-producing East Malartic mine.

All NQ core assays reported above were obtained by standard 50 g fire assaying-AA finish or gravimetric finish at ALS Chemex laboratories in Val d'Or, Quebec. Reported weighted averages were calculated using a minimum of 0.50 g/t Au over successive maximum intervals of 20 metres with no upper cut-off of individual assays. Intersected drifts or lost core within mineralized intersections were incorporated as blank intervals.

Osisko Mining Corp. 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 $145 million on hand and is carrying out an aggressive definition drilling and exploration campaign. An updated NI 43-101 compliant, Measured and Indicated resource estimate on the main Canadian Malartic gold deposit was released on September 8, 2008 and will be filed on SEDAR by mid-October. This updated resource estimate did not include the South Barnat Zone nor any other mineralized zone located outside the main deposit that is currently being evaluated by Osisko.

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 Mining Corporation
    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