Dia Bras Reports More Molybdenum-Copper Mineralization at Its Corralitos Project, Chihuahua State
TORONTO, ONTARIO -- (Marketwire) -- 11/03/11 -- Dia Bras Exploration Inc. (TSX VENTURE: DIB) is pleased to report that final assay results from drilling at the Corralitos project of its Batopilas property, Chihuahua State, Mexico have been received. The results confirm data from a previous release (see release of June 29, 2011) that extensive grades of molybdenum and copper occur in the drilled area. Seventeen holes totaling 4,640.1 m were drilled to test a 500 x 1,500 m area of phyllic alteration. This first phase of drilling will be followed by a second phase to test the mineralized zone laterally and at depth. The Phase 2 program will be designed to explore the mineralized area to the southeast where the core of the mineralized system is believed to occur.
'These are encouraging results,' stated Daniel Tellechea, President & CEO, 'because our drilling demonstrates the presence of extensive molybdenum and copper mineralization from the surface to depth. Moreover, our geologists recognize a potentially-significant zonation to the drill results, which indicates that the Corralitos deposit is possibly larger than we now recognize. We believe this property could contain a molybdenum-copper deposit that could become a significant asset for the Company.'
Drilling at Corralitos was preceded by geologic mapping and extensive surface sampling. In December 2010, the company carried out a trenching and channel sampling program in the entire altered zone, which is related to porphyritic intrusions and visible oxidized mineralization. The program included collection of 400 samples on a grid pattern 50 x 50 m plus outcrop sampling, (Map: http://www.diabras.com/files/media/259ce_CorralitosProject.pdf). Selected results are shown in Table 1 below:
Table 1: Selected Surface Samples
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SAMPLE WIDTH (m) Au g/t Ag g/t Cu ppm Mo ppm
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345121 5 0.084 2.8 786 528
345122 5 0.207 3.6 1065 415
345189 5 0.099 23.9 428 368
345034 5 0.032 4 594 350
345212 5 0.013 2.4 388 302
345062 5 0.104 2.4 1160 273
345139 5 0.062 2.6 2410 237
345137 5 0.092 3.2 2420 230
345267 5 0.013 8.4 79 229
345184 5 0.067 7.7 613 219
345119 5 0.176 11 1660 217
345234 5 0.02 4.3 127 215
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The Phase 1 drilling program was designed to test the surface Mo-Cu anomalies as well as the possibility of silver mineralization in steeply-dipping quartz veins of the type that occur in the region. Because of this, the drill holes in this program are inclined holes, which reveal extensive disseminated and quartz-veinlet-hosted molybdenum and copper mineralization but also show that silver-bearing quartz veins of that type do not occur in the drilled area. As a result, the drill holes in Phase 2 will be vertical holes designed to identify a bulk-tonnage, open-pitable mineralized body.
Assay results are shown in Tables 2 & 3, and individual results for all samples are available on the company's web page, file1 (http://www.diabras.com/files/media/48f4c_Logs_Corralitos.xlsx) and file2 (http://www.diabras.com/files/media/564a0_Corralitos_%20Drill%20Holes%20Samples.xlsx). Individual values range up to 1.14% molybdenum.
Table 2: Newly-Received Assay Results for Corralitos Prospect
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Core
Drill From To Length
Hole #(i) (m) (m) (m) Cu % Mo % W ppm Ag g/t Au g/t
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006 2.30 114.75 112.45 0.073 0.026 121.4 1.19 0.008
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incl. 26.70 35.60 8.90 0.065 0.070 135.5 1.23 0.004
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incl. 42.30 48.15 5.85 0.029 0.053 81.0 1.45 0.009
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and 150.15 153.35 3.20 0.047 0.015 424.5 1.09 0.017
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007 No significant values
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008 No significant values
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009 49.30 306.30 257.00 0.059 0.029 103.9 1.19 0.008
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incl. 204.50 205.70 1.20 0.020 0.598 5.0 2.00 0.035
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incl. 248.05 254.85 6.80 0.013 0.092 49.7 2.78 0.036
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010 53.20 98.10 44.90 0.092 0.005 5.9 2.97 0.053
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011 47.85 94.00 46.15 0.326 0.003 5.8 2.84 0.100
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012 2.50 102.75 100.25 0.346 0.004 8.5 4.59 0.045
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incl. 5.55 11.65 6.10 1.065 0.002 5.0 5.80 0.067
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013 No significant values
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014 28.95 99.00 70.05 0.303 0.021 7.0 2.73 0.042
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incl. 56.00 60.20 4.20 1.040 0.062 5.0 3.50 0.072
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015 No significant values
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016 12.35 108.05 95.70 0.102 0.014 7.7 3.64 0.047
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incl. 21.30 24.70 3.40 0.110 0.055 11.9 1.55 0.019
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incl. 24.05 24.70 0.65 0.119 0.101 20.0 4.80 0.027
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017 4.00 51.00 47.00 0.178 0.014 9.9 3.84 0.038
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(i) Note: all holes have prefix DCO11B
Table 3: Previously-Published(i) Assay Results for Corralitos Prospect
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Drill Core
Hole From To Length
#(ii) (m) (m) (m) Cu % Mo % W ppm(iii) Ag g/t Au g/t
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001 0.00 129.00 129.00 0.029 0.027 80.1 2.55 0.02
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incl. 14.20 32.20 18.00 0.069 0.068 145.7 6.57 0.02
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incl. 11.65 70.40 58.75 0.043 0.042 91.3 2.73 0.01
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002 0.00 126.40 126.40 0.036 0.030 66.9 2.26 0.01
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incl. 14.70 49.15 34.45 0.110 0.060 115.3 3.88 0.02
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003 no significant values
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004 2.50 265.20 262.70 0.062 0.022 116.4 2.13 0.02
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incl. 2.50 163.30 160.80 0.080 0.022 135.3 2.11 0.02
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incl. 5.55 47.05 41.50 0.141 0.051 173.4 2.14 0.01
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005 0.00 202.70 202.70 0.075 0.023 98.4 1.63 0.007
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incl. 136.7 183.7 47 0.045 0.035 149.0 0.764 0.005
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incl. 164 168.5 4.5 0.038 0.076 159.1 1.167 0.006
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(i) see press release of June 29, 2011
(ii) Note: all holes have prefix DCO11B
(iii)not previously published
The Corralitos area is underlain by hydrothermally-altered, coarse-grained granodioritic to monzonitic intrusions and adjacent volcanic and volcaniclastic rocks of probable Cretaceous age. Molybdenum and copper mineralization occurs in these intrusions in veinlets and as disseminations with coarse molybdenite and chalcopyrite, (Drill Core Photo: http://www.diabras.com/files/media/89c1f_drillcore.jpg). Host rocks are intruded by andesitic dykes, both pre- and post-mineralization. A large phyllic alteration zone covering about 900,000 m2 is accompanied by much broader argillic and propylitic alteration. Oxidation creates a conspicuous color anomaly, (Oxilized Area Photo: http://www.diabras.com/files/media/1f480_Oxidizedarea.jpg). The oxidation zone is continuous to about 20 m depth.
Mineralization consists of megascopic and microscopic molybdenite, pyrite, minor chalcopyrite and rare bornite.
The Mo mineralized trend is controlled by the Batopilas fault and has mineralization from the surface to 200 m depth, and is open to the NW, SE, and to depth. Grades of 0.05% to 0.08% Mo are restricted to intervals of 20 m - 50 m. Tungsten values are also higher in this area.
The Cu mineralized trend is controlled by the Tahonas and Corralitos faults, and occurs adjacent and semi parallel to the Mo mineral trend.
The Corralitos deposit is only two km from the village of Batopilas, with access to a regional highway, labor, power grid, etc. These factors will have a significant positive effect on future operation costs.
Method of Analysis
Samples were prepared at the ALS Chemex lab facility in Chihuahua, Mexico, and analyzed at their facilities in Vancouver, Canada. The samples were originally analyzed by ME-ICP41 method, which uses aqua regia digestion but with this method some metal-bearing-minerals may dissolve only partially. Data reported from an aqua regia leach should be considered as representing only the leachable portion of the particular sample.
In order to ensure more complete dissolution of the abundant molybdenite in the samples and a more accurate determination of molybdenum, Dia Bras subsequently ordered all drill core samples from Corralitos to be analyzed by ME-ICP61 method, which utilizes a four-acid digestion process and results in a more complete dissolution of molybdenite, although complete dissolution is not guaranteed.
Selected samples were also analyzed by ME-MS61 method in order to determine contents of elements such as rubidium and lithium with the objective of providing additional geochemical data that will allow the Company's geologists to determine the type of Mo-Cu deposit at Corralitos.
Quality Control
The quality assurance-quality control (QA-QC) program employed by Dia Bras has been described in detail in both RPA's NI 43-101 reports of December, 2006, at Cusi and October, 2005, for Bolivar.
The technical content of this news release has been approved by Thomas L. Robyn, Ph.D., CPG, RPG, a Director of Dia Bras, and a Qualified Person as defined in NI 43-101.
About Dia Bras
Dia Bras Exploration Inc. is a Canadian listed mining company focused on precious and base metals in Peru and Mexico. The Company owns and operates the Yauricocha Mine (Ag-Cu-Zn-Pb) in Central Peru and the Bolivar Mine (Cu-Zn-Ag) in Chihuahua State, Mexico. Dia Bras is also pursuing the development and exploration of the Cusi Property (Ag) and exploring several base and precious metals targets In Peru and Mexico.
Forward-looking Statements
Except for statements of historical fact all statements in this news release without limitation regarding new projects, acquisitions, future plans and objectives are forward-looking statements which involve risks and uncertainties. There can be no assurance that such statements will prove to be accurate; actual results and future events could differ materially from those anticipated in such statements.
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this news release.
Contacts:
Daniel Tellechea
President & CEO
Dia Bras Exploration Inc.
1 (866) 493-9646
Thomas L. Robyn, Ph.D.
Head of Exploration
Dia Bras Exploration Inc.
1 (866) 493-9646