Osisko Mining Corporation

January 30, 2013 08:00 ET

Osisko Intersects 5.5 g/t Au Over 54.0 Metres at Upper Beaver


- Includes 18.7 g/t Au with 1.9% Cu over 11.0 Metres


- New Step Out Hole Intersects 27.7 g/t Au over 4.0 m



MONTREAL, QUEBEC--(Marketwire - Jan. 30, 2013) - Osisko Mining Corporation (TSX:OSK)(FRANKFURT:EWX) is pleased to announce results from the ongoing diamond drill program at the Upper Beaver gold project located in Kirkland Lake, Ontario. The Upper Beaver project is 100% owned by Osisko Mining Ltd., a wholly-owned subsidiary of Osisko.

Highlights from the new holes include 5.5g/t Au over 54.0 metres, including 18.7 g/t Au with 1.9% Cu over 11.0 metres (infill hole UB12-262W3); 16.9 g/t Au over 13.0 metres (infill hole UB12-262W2); and 27.7 g/t Au over 4.0 metres (hole UB12-269W1) in a new step-out.

The tabled results (see below) represent 30 new (and wedge) holes (19,883 metres total drilling) completed in Q4 2012 as part of the in-fill resource definition and step-out exploration program at Upper Beaver.

In-fill Resource Definition

In-fill drilling continues to confirm the continuity and high-grade nature of the core of the deposit. Seven wedge holes on the west portion of the deposit intersected significant mineralization. One hole and three wedges at the -700 m elevation of the deposit returned intervals in the Porphyry Zone assaying 12.8 g/t Au with 0.87% Cu over 9.0 m (including 36.8 g/t Au with 1.48% Cu over 3.0 m) in hole UB12-262; 1.9 g/t Au with 0.18% Cu over 22.7 m in hole UB12-262W1; 16.9 g/t Au with 0.20% Cu over 13.0 m (including 89.9 g/t Au with trace Cu over 2.0 m) in hole UB12-262W2; and 5.5 g/t Au with 0.6% Cu over 54.0 m in hole UB12-262W3. The thick interval in UB12-262W3 includes three sub-zones, 18.7 g/t Au with 1.9% Cu over 11.0 m, 2.3 g/t Au with 0.4% Cu over 14.0 m and 6.5 g/t Au with 0.4% Cu over 7.0 m.

Four wedge holes between -900 m and -1100 m intersected the Porphyry Zone, returning 15.1 g/t Au with 0.6% Cu over 3.0 m (hole UB12-161W9); 3.2 g/t Au with 0.7% Cu over 11.0 m (hole UB12-161W10); 4.2 g/t Au with 0.4% Cu over 6.0 m (hole UB12-161W11); and 3.6 g/t Au with trace Cu over 5.0 m (hole UB12-161W12).

Four holes targeted the Porphyry Zone on the east portion of the deposit. Holes UB12-254 and UB12-254W1 intersected the zone at -600 m below surface, respectively assaying 3.1 g/t Au with 0.3% Cu over 26.0 m (including 9.7 g/t Au with 0.3% Cu over 6.0 m), and 12.6 g/t Au with 0.2% Cu over 6.0 m. Near -400 m depth, hole UB12-259 returned 1.5 g/t over 7.0 m, and UB12-263 returned 4.0 g/t Au over 10.0 m (including 7.1 g/t Au over 5.0 m).

Step-out Exploration

Exploration drilling has intersected significant mineralization east and west of the deposit. Seven wedge holes intersected significant mineralization from near surface to -500 m approximately 50 m west of the existing mineral resource. Significant intersections include 27.7 g/t Au over 4.0 m (hole UB12-269W1); 41.6 g/t Au over 1.0 m and 9.1 g/t Au with 1.1% Cu over 2.0 m (hole UB12-260); 11.0 g/t Au over 1.0 m and 6.2 g/t Au over 4.0 m (hole UB12-265); 10.5 g/t Au over 1.0 m (hole UB12-269); and 0.9 g/t Au with 0.4% Cu over 19.0 m (hole UB12-257).

Six wedge holes intersected significant mineralization (expanding the footprint of the deposit) approximately 100 m - 300 m east of the known mineral resource. Significant intersections returned 5.6 g/t Au over 6.0 m and 3.4 g/t Au over 10.0 m (hole UB12-250W1) at a depth of -700 m; 4.8 g/t Au over 4.0 m (hole UB12-270) near - 150 m depth; and 18.2 g/t Au over 1.0 m (hole UB12-274) near -150 m depth.

About Upper Beaver

The Upper Beaver mine produced approximately 140,000 oz of gold and 12 million pounds of copper intermittently from 1912 to 1971, from 526,678 tonnes averaging 8.31 g/t Au and 1.03% Cu. Queenston commenced exploration on the property in 2005 and defined the first new mineral resource in 2009. Since 2005 three-hundred and eighty new diamond drill holes (including wedges) have been completed on the property, representing 236,874 metres of drilling.

A Preliminary Economic Assessment ("PEA") was completed on Upper Beaver in early 2012 (Queenston press release, February 16, 2012). The PEA studied the economics of building a 2,000 tonne per day mine/mill complex at Upper Beaver that would produce on average 120,000 oz of gold and 5.3 million pounds of copper annually with first production targeted in 2016. The permit to sink a new 1,300 m deep shaft was received in September 2012 and detailed engineering, procurement and shaft collar excavation have commenced. The PEA incorporated the May 2011 mineral resource for Upper Beaver, containing 3,074,000 t averaging 7.0 g/t Au (690,000 oz) with 0.5% Cu (36.6 M lbs) (Indicated) and 3,093,000 t averaging 6.2 g/t Au (616,000 oz) with 0.4% Cu (28.0 M lbs) (Inferred) (Queenston press release, May 4, 2011).

An updated mineral resource was announced on September 2012, increasing the indicated resource by 112% to 6,870,000 t averaging 6.6 g/t Au (1,461,000 oz) and 0.37% Cu (56 M lbs), and increasing the inferred resource by 16% to 4,570,000 t averaging 4.9 g/t Au (712,000 oz) and 0.32% Cu (32 M lbs) (Queenston press release, September 26, 2012).

The focus at Upper Beaver for 2013 will be on the development of the 1,300 metre exploration shaft, including engineering, design and fabrication of the head frame and hoisting facilities. The shaft collar has been established and exploration on the deposit continues with six drills.

Quality Control

All NQ core assays reported were obtained by standard 30 g fire-assaying-AA finish or gravimetric finish at Swastika Laboratories of Swastika, Ontario. Drill program design, Quality Assurance/Quality Control and interpretation of results is performed by qualified persons employing a QA/QC program consistent with NI 43-101 and industry best practices. The Upper Beaver project is supervised by Mark Masson, P.Geo. Standards and blanks are submitted every 25 samples for QA/QC purposes by the Company as well as the lab. Approximately 5% of sample rejects and/or pulps are sent to secondary laboratories for check assaying.

Mr. William McGuinty, P.Geo. is Project Manager for Osisko Mining Ltd. and is the Qualified Person responsible for the technical information reported herein, including verification of the data disclosed.

About Osisko

Osisko Mining Corporation operates the Canadian Malartic Gold Mine in Malartic, Quebec and is carrying out aggressive exploration and project development elsewhere in Canada and Latin America.