Denison Mines Inc.

Denison Mines Inc.

May 12, 2005 08:26 ET

Denison Announces Increased Midwest Reserves

TORONTO, ONTARIO--(CCNMatthews - May 12, 2005) -

Not for distribution to United States newswire services or for dissemination in the United States

Denison Mines Inc. (TSX:DEN) announced today that it has received a new estimate of the Proven and Probable Mineral Reserves at the Midwest Uranium Project totaling 345,500 tonnes at an average grade of 5.47% U3O8, 4.37% Ni and 0.34% Co and containing 41.7 million pounds of U3O8, 33.3 million pounds of nickel and 2.6 million pounds of cobalt. The estimate has been prepared by Roscoe Postle Associates Inc. ("RPA") who was retained by Denison in December 2004 to independently review and audit Denison's Mineral Resources and Mineral Reserves in accordance with the requirements of National Instrument 43-101 (NI 43-101), Companion Policy 43-101CP and Form 43-101F1 of the Canadian Securities Administrators (CSA). RPA is also preparing reserve estimates for the McClean property. Denison owns a 25.17% interest in the Midwest Uranium Project. Denison's share of the Proven and Probable Mineral Reserves at Midwest is 10.5 million pounds U3O8, 8.38 million pounds nickel and 0.65 million pounds cobalt.

The previous estimate of Proven and Probable Mineral Reserves for the Midwest Uranium Project, which was reported by Denison on October 10, 2003, totaled 383,000 tonnes at an average grade of 3.97 % U3O8 containing 33.5 million pounds of U3O8. The increase in the uranium contained in the RPA estimate of Proven and Probable Reserves is attributable to the inclusion of the South Extension Zone also known as the Southern Tail (3.3 million pounds U3O8) and increased estimated U3O8 grades due to the application of a density weighted grade methodology. The latter change has resulted in an increase in average grade of 11%.

Adjusted for Denison's increased interest in Midwest due to the acquisition of a 5.17% interest from Redstone, Denison's previously reported share of the Midwest Proven and Probable Reserves was 8.4 million pounds U3O8 in the aggregate with no estimate made for reserves of nickel and cobalt.

In reporting the new estimate RPA stated that while there are areas of the Mineral Reserve estimate that would meet the classification requirements of Proven they have not estimated the two classes separately. RPA is an independent firm of geological and mining consultants based in Toronto and Vancouver that has been working in the field of Mineral Resource and Reserve estimation since 1985.

The increase in the reserves as calculated by RPA is significant to Denison. The importance of the Midwest Uranium Project to Denison and the other members of the Midwest Joint Venture is substantiated and increased. The cash flow from nickel and cobalt production from Midwest as estimated by RPA, using a conservative value estimate of US$4.00 per pound for nickel and US$10.00 per pound for cobalt, is over CDN$25 million.

James W. Hendry, P. Eng. and Luke Evans, M. Sc., P. Eng. are the Qualified Persons in accordance with the requirements of NI 43-101 who were responsible for the new estimate of the Proven and Probable Mineral Reserves at the Midwest Uranium Project.

An immediate effect of the new reserve estimate on Denison will be a reduction in the depletion rate used for the mill complex to an estimated level of CDN$3.25 per pound of U3O8 produced from CDN$3.91 per pound.

About Denison

Denison Mines Inc. is a uranium exploration, development and production company whose principal assets are a 22.5% interest in one of the world's largest uranium facilities at McClean Lake in Northern Saskatchewan and its 25.17% interest in the Midwest Uranium Project. It is also engaged in mine decommissioning and environmental services through its Denison Environmental Services division. Additional information on Denison is available on SEDAR at and on Denison's website at

Contact Information

  • Denison Mines Inc.
    E. Peter Farmer
    President and Chief Executive Officer
    (416) 979-1991 Ext. 231
    Denison Mines Inc.
    James Anderson
    Executive Vice-President and Chief Financial Officer
    (416) 979-1991 Ext. 372