Osisko Mining Corporation

Osisko Mining Corporation

June 25, 2008 17:17 ET

Osisko Intersects 9.13 g/t Au Average Over 50 Metres at Barnat

MONTREAL, QUEBEC--(Marketwire - June 25, 2008) - Osisko Mining Corp. (TSX:OSK)(FRANKFURT:EWX) is pleased to announce initial results from the definition drill program currently under way on the South Barnat Zone, a separate gold mineralized zone located approximately 1200 metres northeast of the center of the Canadian Malartic deposit. Significant higher-grade intercepts include 9.13 g/t Au over 50 metres (BA08-3002) and 4.73 g/t Au over 23.2 metres (BA08-3001). Detailed results from five new holes are tabled below:

Hole No. Section From (m) To (m) Length (m) Au g/t
BA08-3001 850E 80.0 85.4 5.4 2.71
And 117.0 140.2 23.2 4.73
including 125.0 126.0 1.0 36.70
BA08-3002 850E 128.5 135.0 6.5 5.83
And 155.5 205.5 50.0 9.13
including 188.5 193.0 4.5 30.00
BA08-3007 550E 95.0 109.3 14.3 1.71
BA08-3009 450E 29.5 110.5 81.0 1.51
BA08-3014 700E 153.5 252.0 98.5 2.92
including 205.5 213.0 7.5 7.73

The South Barnat definition drill program is currently focused on an 850 metre-long grid oriented northwest-southeast with sections spaced 50 metres apart. All holes on the grid are inclined 40 to 75 degrees to the northeast or southwest. True widths of the mineralized intersections reported above are estimated at between 50 to 70 percent of the drilled intersections. Drill holes BA08-3003 and BA08-3012 could not penetrate the near-surface backfill of previous mine workings and did not reach their targets. BA08-3004 and BA08-3007 intersected underground mine workings and the former did not intersect significant mineralization. Assay results from other holes are pending.

The new drill intersections and compilation of previous work suggest that the current minimum strike length of the South Barnat Zone is 775 metres with a true width ranging between 30 and 90 metres. South Barnat is open to the northwest and southeast and extends to a minimum depth of 250 metres.

Osisko holes previously drilled and reported in South Barnat are summarized below including their easting along the grid:

Hole No. Section From (m) To (m) Length (m) Au g/t
CM06-1004 300E 24.2 71.3 47.1 2.23
CM06-1005 250E 33.2 100.6 67.4 3.66
CM06-1006 200E 106.2 117.7 11.5 3.56
CM06-1007 125E 52.1 109.7 57.6 4.11
CM06-1008 75E 14.5 128.0 113.5 1.01
CM07-2008 625E 9.8 49.9 40.1 1.73
And 71.7 113.5 41.8 3.07
CM07-2030 650E 56.5 167.7 111.2 1.89

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 disseminated gold mineralization is hosted both in silicified greywackes of the Pontiac Group (south of the fault contact) and in schistose, carbonatized 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 locally containing visible gold. Current modeling suggests that gold mineralization in the South Barnat Zone may extend further east along the north and south walls of the past-producing East Malartic mine.

Sean Roosen, Osisko's President and CEO stated: "Osisko's current exploration objective is to define new higher-grade resources for potential blending with mineralization from the main Canadian Malartic deposit. We are focusing the bulk of current exploration drilling on the South Barnat Zone because of earlier results in 2006 that suggested this zone was potentially twice the average grade of the Canadian Malartic deposit. Today's new drill results support this view and suggest potential for even higher grade material, which could have a very positive effect on the Canadian Malartic project parameters."

The Company also wishes to announce the completion of the 25,000 metre condemnation drill program. All drill core has now been processed and no significant gold mineralization was noted. These results clear the way for the completion of design and planning for the areas slated for potential development of the water pond, tailings impoundment and mill complex.

With the recent completion of the drilling, logging, sampling and assay work on the infill drill program and the now completed 25,000 metre condemnation program, all drilling work on the main deposit and project footprint site has been completed. Drilling on the property is now targeting areas for potential additional resources (South Barnat, Jeffrey, Shaft) as well as grass roots targets. Drilling is now proceeding at a rate of approximately 12,000 metres per month (from a high of 33,000 metres in February) to allow core production to proceed in pace with necessary laboratory assay turn-around times.

Osisko will host a conference call tomorrow, Thursday, June 26 at 10:30 am EST for shareholders wishing to discuss results from South Barnat. Participants wishing to join the call may dial in at: Local / International: 416-850-9144 or North American Toll- Free: 1-866-400-3310.

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.

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 $160 million on hand and is carrying out feasibility component studies as well as an aggressive definition drilling and exploration campaign. The Company is expecting to release an updated NI 43-101 compliant, measured and indicated resource estimate on the main Canadian Malartic gold deposit by mid-July 2008.

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 Corp.
    John Burzynski
    Vice-President Corporate Development
    Osisko Mining Corp.
    Daniel Boase
    Investor Relations
    416-742-5600 / Toll Free: 1-866-580-8891