Detour Gold Corporation reported its 2011 year-end mineral reserve and resource update for its 100% owned Detour Lake gold project in northeastern Ontario. The update includes 78% of the 2011 drilling program of 86,644 metres, which was aimed at converting inferred resources into reserves within the previous open pit. A 5% increase in proven and probable open pit reserves from 14.9 to 15.6 million ounces; A 13% increase in global measured and indicated mineral resources from 20.5 to 23.3 million ounces (inclusive of mineral reserves), and an additional 5.8 million ounces in the inferred category; Life of mine (LOM) increased to 22 years from 21 years at mill throughput ranging from 55,000 to 61,000 tpd; and Reduction of 8% in the strip ratio from 3.9 to 3.6. The database for this update incorporated 67,587 metres (or 78%) of the Detour Gold 2011 drilling campaign, available drilling data from section 16,500E to 17,000E from previous operators, and all previous drilling data included in the 2010 year-end update for a total of 1,134,287 metres of drilling in 6,475 holes, of which 523,270 metres is from Detour Gold's drilling campaigns. The Ordinary Kriging (OK) block model used for the global mineral resources covers the area between sections 16,500E and 20,600E, extending an additional 500 metres to the west from the 2010 year-end block model. The open pit mineral reserves were estimated within the same detailed engineered pit design used in the 2010 year-end update by using the measured and indicated resources at a cut-off grade of 0.5 g/t. Optimization parameters used for the mineral reserve estimate were identical to the 2010 year-end update. In the pit design, inter-ramp pit slopes vary from 49 to 56 degrees depending on rock type and structure orientation. The mineral reserves were estimated in MineSight with the kriged block grades that include an estimated dilution of 11.7%. The estimated proven and probable reserves total 15.6 million ounces, after using a 95% mining recovery rate and an additional mining dilution of 3.8%. The stripping ratio (waste to ore) decreased by 8% from 3.9 to 3.6 as a result of converting waste and inferred resources into reserves.