Largo's Updated Mineral Resource Estimate Defines Higher-Grade Zone at Northern Dancer Project, Yukon
3/12/2009 9:38:41 AM - Market Wire
- Tonnage of new Measured and Indicated mineral resource estimate has increased by 58%
- Contained pounds of Tungsten (WO3) and Molybdenum (Mo) in the new Measured and Indicated mineral resource estimate have increased by 56.5% and 76% respectively
- The grade of Tungsten (WO3) and Molybdenum (Mo) in the higher-grade zone has increased by 35% and 70% respectively over the total deposit grade
- Combined improvement in grade and understanding of factors affecting recovery and mineralogy encourages Largo regarding future economic viability of the project
TORONTO, ONTARIO, Mar 12, 2009 (Marketwire via COMTEX News Network) --
Largo Resources Ltd. (TSX VENTURE:LGO) has completed a new block model and updated mineral resource estimate incorporating the results from its 2008 drill program consisting of 38 holes totalling 11,509 metres, the results from the 2007 and 2006 drill programs completed by Largo and historical drilling results for the Northern Dancer deposit, which is located in the south-central region of the Yukon Territory in north-western Canada. The updated mineral resource for the deposit at a cut-off grade of 0.06 % WO3 is estimated as Measured mineral resources of 30.8 million tonnes grading 0.114% WO3 and 0.030% Mo, Indicated mineral resources of 192.6 million tonnes grading 0.100% WO3 and 0.029% Mo. The Measured and Indicated mineral resource estimate contains 500.1 million pounds of WO3 (226.9 k tonnes) and 143.8 million pounds of Mo (65.2 k tonnes). Inferred mineral resources were estimated to be 201.2 million tonnes grading 0.089% WO3 and 0.024% Mo containing 393.1 million pounds of WO3 (178.3 k tonnes) and 107.7 million pounds of Mo (48.9 k tonnes). The grade of WO3 and Molybdenum has increased by 14% and 15% respectively in the new Measured mineral resource estimate compared to the previous Indicated mineral resource estimate (see press release April 9, 2008). The tonnage of the new Measured and Indicated category has increased by 58% compared to the previous Indicated mineral resource estimate (see press release April 9, 2008). While the contained pounds of WO3 and Molybdenum have increased by 56.5% and 76% respectively. Most importantly, the 2008 drilling program provided much better definition of the higher-grade zone which is estimated to contain a Measured and Indicated resource of 60.3 million tonnes grading 0.137% WO3 and 0.045% Mo (WO3 equiv 0.215%) and Inferred mineral resource of 5.4 million tonnes grading 0.134% WO3 and 0.047 % Mo (WO3 equiv 0.214%) at a 0.17% WO3 equivalent cut-off grade. These estimates represent grade increases of 35% and 70% over the overall deposit grade for both WO3 and Molybdenum respectively. The drilling indicates that the higher grade zone averages 50 metres in width, extends along strike for approximately 1,200 metres and extends from surface to an average depth of 350 vertical metres. This higher grade zone is consistently mineralized over the full extent drilled to date and is open along strike to the southwest and at depth. Soil geochemical work indicates that the mineralized system likely extends for at least a further 400 metres along strike. Andy Campbell, Vice-President, Exploration of Largo, stated: "Significant changes have resulted from the 2008 drill program which was very successful at upgrading the resource and confirming the significant high grade zone from the previous estimate reported on April 9, 2008. One of the most obvious changes is the substantial increase in the grade of molybdenum throughout the deposit from a modest 15% increase to as much as a 70% increase depending on the category and higher-grade zone. Northern Dancer is primarily a tungsten deposit, however, molybdenum is a significant contributor to the deposit and needs to be included and Largo believes that it is preferable to refer to the grade as a tungsten equivalent. The other significant area of change was the 59% increase in the Measured and Indicated tonnage from that previously reported in April 8, 2009. The deposit now has a substantial Measured and Indicated resource that includes the higher-grade zone which could support a pre-feasibility study." Mineral Resources are presented in Table 1 below for the overall deposit for each resource category, as well as for the higher grade tungsten and molybdenum zone, which are included within the overall resource. The cut-off grade was determined based on comparison to similar deposit types that are being mined or planned to be mined by open pit methods, but has not been confirmed by appropriate economic studies. Table 1: Mineral Resources in the Northern Dancer Deposit, as at March 1, 2009(i), based on 0.06 % WO3 cut off grade. WO3 Mo WO3 Mo Million % % Tonnes Tonnes Million Million Category Tonnes WO3 Mo ((i)000) ((i)000) lbs. lbs. Measured 30.8 0.114 0.030 35.1 9.1 77.3 20.1 Indicated 192.6 0.100 0.029 191.8 56.1 422.8 123.7 Measured & Indicated 223.4 0.107 0.029 226.8 65.3 500.1 143.9 Inferred 201.2 0.089 0.024 178.3 48.9 393.1 107.7 Table 2: Mineral Resources in the Northern Dancer Deposit (Higher grade shell(ii)) as at March 1, 2009(i), based on 0.17% WO3 equiv cut-off grade(iii). % WO3 Mo WO3 Mo Million % % WO3 Tonnes Tonnes Million Million Category Tonnes WO3 Mo Equiv ((i)000) ((i)000) lbs. lbs. Measured & Indicated 60.3 0.137 0.045 0.215 82.8 45.1 182.6 59.6 Inferred 5.4 0.134 0.047 0.214 7.2 4.2 15.8 5.5 Notes: (i) The above resource classifications conform to CIM Standards on Mineral Resources and Reserves referred to in National Instrument 43-101. Although 0.06% WO3 is considered a likely cut-off grade for this deposit, based on comparisons with other similar deposit types, it has not been confirmed by the appropriate economic studies. Totals may not add up exactly due to rounding. (ii) Higher grade shell includes high grade Mo and WO3 zone and is seated within the overall Mineral Resource. (iii) The WO3equiv cut-off grade calculated was based on Mo Price at 12 $ /LB; WO3 price at 9.07 $ /LB; 80 % Mo recovery and 65% WO3 recovery with this formula: WO3equiv equals WO3 % + 1.736 x Mo %. The Northern Dancer deposit is one of the world's largest known tungsten-molybdenum porphyry systems. The mineralization is hosted in fractures, veinlets and veins associated with a northeast-trending sheeted vein structure hosted in calc-silicate (skarn) rocks and spatially related to a felsic intrusion (quartz-feldspar porphyry). The deposit, which has been tested by drilling for 1.2 kilometres along strike, 500 metres vertically and 600 metres in width, remains open along strike to both the northeast and southwest as well as at depth. At Northern Dancer, tungsten and molybdenum mineralization are concentrated in two zones which partially overlap. In the core of the deposit, there is a higher grade molybdenum zone where molybdenite occurs within and adjacent to the felsic intrusion. Surrounding and partially overlapping the molybdenum zone is a much more extensive tungsten zone where scheelite occurs in northeast-trending sheeted quartz veins structures. The Mineral Resource estimate was generated using lithological, mineralogical, Mo and WO3 assay data from 121 drill holes totalling 33,700 m of drilling. The deposit was modeled into several estimation domains using the Gemcom mining software. Cap cut only applied for Mo at 0.7 % for the skarn domain and WO3 at 0.106 in monzonite based on a statistical analysis. Samples were composited over 5 m intervals. Mo and WO3 grades were interpolated into estimation domains using Ordinary Kriging. The Mineral Resource estimate has been prepared by Largo Resources, and reviewed and validated by Dr. Warwick S. Board, MAusIMM, Pr.Sci.Nat., Senior Consultant with Snowden Mining Industry Consultants Inc. ("Snowden"). Dr. Board, a qualified person as defined under National Instrument 43-101, visited the site from July 5 to 7, 2008 and prepared the previous resource estimate. Dr Board has verified the scientific and technical information contained in this news release. Assaying for the 2008 drill program was carried out by Acme Analytical Laboratories Ltd., an ISO 9000:2000 certified laboratory in Vancouver, British Columbia. The samples are crushed to 70% passing 10 mesh, split to 250 g and pulverized to 95% passing 150 mesh. A 5 g split is analyzed for Mo and W using a phosphoric acid leach followed by ICP-emission spectrometry. A second 5 g split is analyzed for 36 elements by ICP-mass spectrometry using a hot (95 degrees C) aqua regia leach. Routine check assays are performed on sample rejects by SGS. Mr. Andy Campbell, P.Geo. is the Qualified Person as defined under National Instrument 43-101 responsible for the scientific and technical work on the program. As a result of the encouraging results of the mineral resource update, Largo is currently defining a further programme of engineering investigation with the objective of designing an economically viable project. The major steps in this process are expected to include : - Undertaking pit optimization and initial mine planning based on the new mineral resource with the associated higher grades - Identifying higher grade zones that will form the "key" material to be milled in the first few years of the mine operation so as to enhance the project economics - Conducting metallurgical testwork on composite samples representing this "key" material with a view to optimising recovery as a function of grind size, mineralogy and other factors - Build on the metallurgical testwork carried out to date to define the recovery and grade of the tungsten and molybdenum concentrates to be produced. Currently, Largo anticipates that the tungsten concentrates will be produced through a combination of gravity and flotation techniques, and the molybdenum concentrate by flotation. This will be done after an initial stage of pre-concentration using optical sorting employing fluorescent light and/or ultra violet light. Overall, the testwork will be targeted to develop a practical process flowsheet to the standards demanded by a preliminary feasibility study. Testwork will further produce metallurgical and other data that will be required for engineering design and financial analyses. Mark Brennan, President of Largo, stated, "The combination of improved grades and the enhancement of our existing understanding of the factors affecting recovery and mineralogy of the deposit encourages Largo management regarding the future economic viability of the project." About Largo Largo Resources is a Canadian natural resource development and exploration company with two advanced stage projects: the Maracas Vanadium-PGM deposit in Brazil and the Northern Dancer Tungsten-Molybdenum deposit in the Yukon. The company is listed on the TSX Venture Exchange under the symbol LGO. For more information please refer to Largo's website: www.largoresources.com. Disclaimer This press release contains forward-looking statements under Canadian securities legislation. Forward-looking statements include, but are not limited to, statements with respect to the Largo's development potential and timetable of the Northern Dancer project; the Largo's ability to raise additional funds necessary; the future price of tungsten and molybdenum ; the estimation of mineral reserves and mineral resources; the timing and amount of estimated future exploration; costs of future activities; success of exploration activities; government regulation of mining operations; and environmental risks. Generally, forward-looking statements can be identified by the use of forward-looking terminology such as "plans", "expects" or "does not expect", "is expected", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates" or "does not anticipate", or "believes", or variations of such words and phrases or statements that certain actions, events or results "may", "could", "would", "might" or "will be taken", "occur" or "be achieved". Forward-looking statements are based on the opinions and estimates of management as of the date such statements are made. Estimates regarding mineral resources are based on extensive analysis regarding exploration information obtained for diverse sources, including drill results; such analysis being conducted by company geologists and verified by third party consultants. Forward-looking statements are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of the Largo to be materially different from those expressed or implied by such forward-looking statements. Although management of the Largo has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. The Company does not undertake to update any forward-looking statements, except in accordance with applicable securities laws. SOURCE: Largo Resources Ltd. Largo Resources Ltd. Mark Brennan President & CEO (416) 861-5886 Email: mbrennan@largoresources.com Website: www.largoresources.com Copyright (C) 2009 Marketwire. All rights reserved. -----------
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