DOT Announces New Copper Discovery
Wednesday, Mar 10, 2010
DOT Resources Ltd. is pleased to announce that it has made a new copper discovery on its 100% owned Dot porphyry copper property (the "Property") located 17 kilometres south of the Highland Valley Mining District, in central British Columbia.
SUMMARY
In October 2009, DOT commenced a drilling program with the objective of testing a number of geophysical targets that were interpreted to be areas of copper mineralization. After very encouraging visual inspection of core, DOT decided to expand its drilling program into 2010 to take advantage of what the Corporation believed to be other highly perspective targets. Eight of 15 diamond drill holes ("DDH") targeted one of those geophysical targets, the West Zone. The analytical results for those 8 DDH have now been received.
These 8 DDH have resulted in the discovery of a new zone of copper mineralization characterized by widespread, fracture controlled and disseminated native copper mineralization in potassic and argillic altered granodiorite. Native copper mineralization has been intersected over an area that measures 800 metres ("m") by 300 m and is open along the interpreted strike and width. Native copper is the only copper mineral intersected in the West Zone. In contrast, the Southeast Zone, located 700 m to the east of the West Zone contains chalcopyrite-bornite mineralization which suggests that two separate porphyry style mineralizing events have occurred within this area of the DOT property.
West Zone
Six of the eight DDH intersected significant copper-silver mineralization. Each mineralized hole intersected two zones of copper-silver-gold mineralization typically with a narrower higher grade zone within the broader mineralized interval. One hole failed to reach bedrock and one hole did not intersect significant copper mineralization. Trace concentrations of native copper was observed throughout the core for the six mineralized DDH resulting in a high (greater than 400 parts per million) copper background concentration. The weighted average grade of the mineralized intervals in the West Zone was estimated using a 0.05% copper cut-off grade.
The weighted average grade of the mineralized interval in DDH-DOT-09-W-02 from 168.19 m to 183.95 m is influenced by a 3 m interval that assayed 1.76% copper and 7.76 grams per tonnes ("g/t") silver. The interval from 51.20 m to 91.36 m in DDH-DOT-09-W-03 is influenced by a 6 m interval that assayed 1.69% copper and 6.72 g/t silver.
Diamond Drilling and Sampling Procedures
Diamond drilling is completed using a 76 mm diameter core barrel. The average core recovery is estimated to be greater than 96% although recoveries of 50% were recorded over narrow (less than 5.0 m) intervals. The cores were split using a manual splitter and one half of the core was collected for sample preparation and analysis and the other half is retained for future reference. Sample intervals were selected based on lithologies and intensity of alteration. The sample intervals varied between one and two metres and sample weights ranged from 2.0 to 4.0 kilograms respectively.
Sample preparation was completed by EcoTech Laboratories ("EcoTech") located in Kamloops, British Columbia using the following procedure: Core samples are prepared using a 2 stage crushing on a jaw crusher to 70% passing 10 mesh screen. A 250 gram sub-sample of the crushed material is pulverized on a ring mill to 95% passing minus 150 mesh screen. The sub sample is rolled and homogenized.
After initially analyzing the samples on the ICP/MS all samples with greater than 1,000 ppm copper are assayed using the Aqua Regia Assay method.
A metallic preparation was also used to determine copper concentration in the core samples from the West zone. Rock samples are two stage crushed to minus 10 mesh, then split to achieve a 1,000 gram (approximate) sub sample. The sample is pulverized to 95% -140 mesh. The sample is weighed, then rolled and homogenized and screened at 140 mesh.
The -140 mesh fraction is homogenized and 2 samples are digested for a Cu assay. The +140 mesh material is assayed entirely. The sample is digested with an aqua regia digestion in 200 ml phosphoric acid flasks. The digested solutions are made to volume with RO water and allowed to settle. They are analyzed on a Perkin Elmer atomic absorption machine using air-acetylene flame to 0.01 grams/t detection limit. The values are calculated back to the original sample weight providing a net copper value as well as 2-140 values and a single +140 mesh value.
Gold analyses are completed on a 30 gram sample and a repeat sample is completed for every 10 samples. The samples are fused along with proper fluxing materials and the resulting bead is digested in Aqua Regia and analyzed by atomic absorption. Over-range values are re-analyzed using gold assay methods. (Detection limit 1-5 ppb AA). EcoTech has a 9001 International Standard Organization ("ISO") rating and is independent of DOT.
ABOUT DOT
DOT is a Canadian corporation currently focused on the exploration and development of its copper property in central British Columbia. The Corporation is planning to assess future copper and copper-gold properties for exploration and development opportunities throughout North and South America.
DOT shares trades on the TSX Venture exchange under the symbol DOT. The Corporation's website can be accessed at www.dotresourcesltd.com.
Source: Marketwire




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