Osisko Mining Corporation

Osisko Mining Corporation

December 20, 2006 17:25 ET

Osisko Drilling Extends Canadian Malartic Deposit to 1.8 km Strike Length

MONTREAL, QUEBEC--(CCNMatthews - Dec. 20, 2006) - Osisko Exploration Ltd. (TSX VENTURE:OSK), (Deutsche Boerse:EWX) is pleased to announce new results from the definition drilling program at its 100%-owned Canadian Malartic gold property. Seven new holes (tabled below) focused on the Sladen extension of the deposit and have produced significant new mineralized intercepts, including 76.0m averaging 1.70 g/t Au (CM06-840), 55.9 m averaging 2.46 g/t Au (CM06-842) and 149.0m averaging 0.81 g/t Au (CM06-836).

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

CM06-835 4580E 15.1 60.1 45.0 0.69
CM06-836 4580E 25.5 174.5 149.0 0.81
CM06-840 4820E 15.5 91.5 76.0 1.70
including 86.0 91.5 5.5 4.31
CM06-842 4880E 17.1 73.0 55.9 2.46
including 36.5 45.5 9.0 5.62
CM06-844 5000E 254.0 280.0 26.0 1.37
CM06-846 5000E 61.7 81.2 19.5 1.15
CM06-848 4760E 2.5 49.2 46.7 1.40

Drill holes CM06-841 (section 4820E) and CM06-850 (section 4940E) were collared in porphyry, north of the projected Sladen mineralized zone, and did not intersect significant mineralization.

The new drilling confirms the length extension of the Canadian Malartic deposit to section 5000E, for a total strike length of 1800 metres. The true width of the deposit at this eastern extremity has not yet been determined. Historical data indicates that the mineralized system continues eastward beyond section 5000E for an additional minimum distance of 1450 meters. Previous exploration drilling in the Pontiac sediments south of this extension has been shallow and sporadic, and Osisko considers this corridor to be highly prospective. These areas will be the target of extensive exploration drilling by Osisko in 2007.

Eight holes from the Phase Eight infill program in the western portion of the deposit are also tabled below. CM06-834 and CM06-843 tested the northern extremity of the deposit on sections 3610E and 3674E, respectively. CM06-845 and CM06-849 tested for mineralized offshoots at the southern extremity of the deposit on sections 3850E and 3790E, respectively. Drill holes CM06-837, CM06-839 and CM06-847 tested for remnant mineralization above underground mine workings.

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

CM06-834 3610E 244.5 300.0 55.5 0.68
CM06-837 3730E 175.6 196.7 21.1 1.09
CM06-838 4060E 225.6 248.1 22.5 0.85
CM06-839 3850E 252.9 261.7 8.8 3.05
CM06-843 3674E 154.0 251.5 97.5 0.76
CM06-845 3850E 55.8 97.8 42.0 0.75
CM06-847 3730E 88.2 111.0 22.8 1.81
and 137.0 147.5 10.5 1.55
CM06-849 3790E 9.2 25.7 16.5 0.79
and 84.2 94.7 10.5 0.74

To date Osisko has completed over 90,000 metres of drilling on the Canadian Malartic property. The Phase Eight definition program has been increased to a total of 26,000 metres, which will result in a total of approximately 100,000 metres drilled on the property by year end. The Canadian Malartic gold deposit is being evaluated for large-scale open pit, bulk-tonnage mining potential. A preliminary NI 43-101 compliant, inferred gold resource estimation on the main deposit was recently released (see December 6, 2006 press release) and ongoing drilling will lead to an upgraded inferred resource calculation in early 2007. Metallurgical test work is also in progress with results expected to be available in January 2007.

All NQ core assays were conducted using 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 0.40 g/t Au over successive 20 metre intervals with no upper cut-off of individual assays. 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 or Toll Free: 1-866-580-8891
    Osisko Exploration Ltd.
    Daniel Boase
    Investor Relations
    416-742-5600 or Toll Free: 1-866-580-8891