Detour Gold Updates Reserves to 14.9 Million Ounces at Detour Lake
Highlights (base case using
-- A 31% increase in proven and probable open pit reserves from 11.4 to 14.9 million ounces -- A 16% increase in global measured and indicated mineral resources to 20.5 million ounces (inclusive of mineral reserves), and an additional 5.1 million ounces in the inferred category -- Life of mine (LOM) increased to 21 years from 16 years at mill throughput ranging from 55,000 to 61,000 tpd -- Initiating economic studies to evaluate an increase in process plant throughput
"This significant reserve increase and the high potential of finding more ounces from additional drilling support our organic growth strategy. The positive impact of the 2010 drilling campaign extended the
"
Detour Lake Mineral Resources
The database for this update incorporated new drilling data from the 2010 drilling campaign (98,934 metres of 107,000 metres) and all the drilling data from the feasibility study for a total of 985,848 metres of drilling in 6,047 holes, of which 435,563 metres is from
The Ordinary Kriging (OK) block model used for the global mineral resources covers the area between sections 17,000E and 20,600E, extending an additional 500 metres to the west from the feasibility study block model. The following improvements were made to the
Detour Lake Global Mineral Resource Estimate(1) Resource Cut-off Grade Tonnes Grade Capped(2) Gold Ounces Category (g/t) (millions) (g/t Au) (000's) ---------------------------------------------------------------------------- Measured (M) 0.3 152.3 1.18 5,784 0.4 137.4 1.27 5,617 0.5 123.6 1.36 5,417 ---------------------------------------------------------------------------- Indicated (I) 0.3 741.3 0.78 18,497 0.4 588.0 0.89 16,786 0.5 470.6 1.00 15,098 ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- Total (M&I) 0.3 893.6 0.85 24,282 0.4 725.4 0.96 22,403 0.5 594.2 1.07 20,515 ---------------------------------------------------------------------------- Inferred 0.3 375.7 0.62 7,444 0.4 264.9 0.73 6,214 0.5 190.3 0.84 5,144 ---------------------------------------------------------------------------- (1) Mineral reserves are included within the mineral resources reported. (2) Capping grade estimated by domains and varies from 15 g/t to 50 g/t.
MineSight software was used to generate an optimum pit shell using the Lerchs-Grossman (LG) pit optimizer algorithm based on the measured and indicated resources only, using the same economic parameters established by the
Detour Lake In-pit Mineral Resource Estimate(1) Resource Cut-off Grade Tonnes Grade Capped(2) Gold Ounces Category (g/t) (millions) (g/t Au) (000's) ---------------------------------------------------------------------------- Measured (M) 0.3 135.2 1.18 5,134 0.4 123.1 1.26 4,997 0.5 111.2 1.35 4,825 ---------------------------------------------------------------------------- Indicated (I) 0.3 583.1 0.76 14,329 0.4 462.0 0.87 12,977 0.5 367.9 0.98 11,624 ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- Total (M&I) 0.3 718.3 0.84 19,463 0.4 585.1 0.96 17,973 0.5 479.1 1.07 16,449 ---------------------------------------------------------------------------- Inferred 0.3 36.7 0.56 658 0.4 21.5 0.71 489 0.5 14.2 0.84 386 ---------------------------------------------------------------------------- (1) Mineral reserves are included within the mineral resources reported. (2) Capping grade estimated by domains and varies from 15 g/t to 50 g/t.
Detour Lake Mineral Reserves
The open pit mineral reserves were estimated within a detailed engineered pit design by using the measured and indicated resources at a cut-off grade of 0.5 g/t. In the pit design, inter-ramp pit slopes vary from 49 to 56 degrees depending on rock type and structure orientation. The block model was prepared in MineSight with the kriged block grades that include an estimated dilution of 11.7%. The estimated proven and probable reserves total 14.9 million ounces, after using a 95% mining recovery rate and an additional mining dilution of 3.8%. The stripping ratio (waste to ore) has increased to 3.9 from 3.3 as a result of a greater quantity of waste (including inferred resources) contained within the new pit design due to insufficient drilling at the west end of the pit. In all drilling programs to date, the Company has had a very high success rate in converting inferred resources to the measured and indicated categories (and reducing strip ratio). It is anticipated that the 2011 drilling program will be as successful in proving the continuity of the gold mineralization, resulting in a conversion to mineral reserves and a lower strip ratio.
A summary table of the changes from the feasibility study is shown below.
Summary of Changes in Mineral Reserves fromJune 2010 (FS) toJanuary 2011 Feasibility Study New Update % Change ------------------------------------------------------------------------ Total P&P gold reserves (Moz) 11.4 14.9 +31% ------------------------------------------------------------------------ Tonnage (Mt) 347.5 451.4 +30% ------------------------------------------------------------------------ Grade (g/t) 1.02 1.03 +1% ------------------------------------------------------------------------ Strip ratio 3.3 3.9 +18% ------------------------------------------------------------------------ Mine life 16 21 +31% ------------------------------------------------------------------------ Estimated gold recovery (%) 91.2 91.0 - ------------------------------------------------------------------------ Gold price (US$/oz) 850 850 - ------------------------------------------------------------------------ Exchange rate 1.10 1.10 - ------------------------------------------------------------------------ Detour Lake Mineral Reserves at$850 /oz (cut-off grade of 0.5 g/t) Reserve Tonnes Grade Gold Ounces Category (millions) (g/t Au) (000's) ----------------------------------------------------------------------- Proven 93,715 1.29 3,886 Probable 355,838 0.96 10,974 ----------------------------------------------------------------------- Total (P&P) 449,553 1.03 14,860 -----------------------------------------------------------------------
The Company's strategy remains, as per the feasibility study, to develop the mining schedule using an elevated cut-off grade through the early years for a higher head grade to be processed at the plant facility.
Capital Costs Status
Pre-production capital costs remain in line with the feasibility study. The Company has entered into commitments for approximately
Economic Studies to Start
With a solid reserve base of nearly 15 million ounces,
-- An increase in mill capacity (processing plant expansion) - initiating a tonnage rationalization study to evaluate throughput options between 75,000 and 100,000 tpd (note that the purchased gyratory crusher is already designed for higher capacity); -- AtUS$1,000 /oz or above and once the plant expansion is completed, the Company could mine economically at a lower gold cut-off grade and generate higher mineral reserves; -- Engineering work optimization (i.e. pit slope improvements, potential in-pit dumping of additional waste and tailings); -- Additional drilling to convert inferred resources into measured and indicated resources in the current pit to reduce strip ratio; and -- Continue drilling campaign to test the western extension of the deposit (i.e. 50,000 metres planned in 2011).
For a potential expansion to proceed, the Company may be required to obtain additional authorizations or permits beyond those currently received or being sought to accommodate for a larger open pit operation.
Qualified Persons
The mineral resources for
A NI 43-101 compliant Technical Report will be filed on the Company's website and on SEDAR within 45 days.
Conference Call
-- InCanada andthe United States dial toll free 1-877-240-9772 -- International 416-340-2216 -- To listen to the audio webcast live online, go to: www.detourgold.com (home page) and click on "Conference Call Audio WebcastFebruary 1, 2011 " under "Events" or go directly to www.gowebcasting.com/2195.
The conference call will be recorded and playback of the call will be available after the event by dialing toll free in
Forward-Looking Information
This press release contains certain forward-looking information as defined in applicable securities laws (referred to herein as "forward-looking statements"). Specifically, this press release contains forward-looking statements regarding results and projections based on the assumptions and parameters contained in the
Such forward-looking statements are also based on a number of assumptions which may prove to be incorrect, including, but not limited to, assumptions about the following: the availability of financing for exploration and development activities; the estimated timeline for the development of the
Information Concerning Estimates of Mineral Reserves and Resources
The mineral reserve and resource estimates reported in this press release were prepared in accordance with Canadian National Instrument 43-101Standards of Disclosure for Mineral Projects ("NI 43-101"), as required by Canadian securities regulatory authorities. For
Contacts:Detour Gold Corporation Gerald Panneton President and CEO (416) 304.0800Detour Gold Corporation Laurie Gaborit Director Investor Relations (416) 304.0581Detour Gold Corporation Royal Bank Plaza South Tower ,200 Bay Street , Suite 2200,Toronto, Ontario M5J 2J1
Source: