Dia Bras Exploration Inc.
TSX VENTURE : DIB

Dia Bras Exploration Inc.

April 06, 2009 08:38 ET

Dia Bras Exploration Inc.: New Discovery of Disseminated Copper Silver Mineralization as a Potential Open Pit Target at the Bolivar Mine

MONTREAL, QUEBEC--(Marketwire - April 6, 2009) - Dia Bras Exploration Inc. (TSX VENTURE:DIB) ("Dia Bras" or the "Corporation") is pleased to announce that exploration teams of its wholly owned Mexican subsidiary, Dia Bras Mexicana S.A. de C.V. encountered six areas of disseminated copper-silver skarn mineralization during on-going geologic studies, mapping, sampling, and drilling at its Bolivar mine, Chihuahua, Mexico. Copper-silver mineralization crops out in skarnitized carbonate rocks at their contact with the Piedras Verdes granodiorite stock and extends for two kilometers from Bolivar Northwest at the north end of the Bolivar District to El Gallo at the current southern limit of district exploration (See following Location Map).

To view the Location Map - Disseminated Copper-Silver Mineralization at the Bolivar Mine, Chihuahua, Mexico: http://www.diabras.com/en/newscenter/2009/DIBPr15_Figure1_DisseminationCuAg.pdf

Daniel Tellechea, President and Chief Executive Officer, says "The significance of these areas is not the resources currently defined but the potential that exists between them. Together these areas suggest that copper-silver mineralization continues for over two kilometers on surface and that presents potential for an open-pittable copper-silver resource." Exploration during 2009 is planned to sample and drill both the known resources and intervening ground to explore this target.

Currently Dia Bras operates the Bolivar underground pilot mining operation from two surface adits at the Bolivar Mine. Mining is advancing in skarn down-dip to the east, exploiting massive copper-zinc skarn mineralization that ranges from 2-12% copper and 5-40% zinc. However, it is the disseminated mineralization described in this release that presents potential for a low-cost, open-pit mining operation to feed Dia Bras' proposed new on-site mill (See Disseminated Copper Silver Progress Report).

At the northernmost areas, Bolivar NW and Rosario, north--south trending, disseminated chalcopyrite mineralization crops out over a 20-50 meters width, a 60-80 meters thickness and is open to the north and south along strike of the garnet-pyroxene skarn. Thus far exploration has defined Measured and Indicated resources shown in the table below (see September 25, 2008 SGS Geostat Resource Estimate in February, 2009 Bolivar Technical Report):


-----------------------------------------------------------------------
-----------------------------------------------------------------------
Resources Cu Zn Au Au
Areas Categories Tonnes % % gm/mt gm/mt
-----------------------------------------------------------------------
Bolivar NW Measured & Indicated 146,300 0.61 1.44 0.24 16.8
-----------------------------------------------------------------------
Rosario Measured & Indicated 17,200 0.66 6.18 0.1 17.1
-----------------------------------------------------------------------
-----------------------------------------------------------------------


The furthest hole north of Bolivar NW, DB04B026 advanced 277 meters northwest inclined 62 degrees through hornfelthized andesite and encountered disseminated and veinlet controlled chalcopyrite-pyrite in mixed dark garnet skarn and light green pyroxene hornfels. The hole encountered the following mineralization that suggests disseminated copper-silver mineralization continues further to the north under andesite.



----------------------------------------------------------------------
----------------------------------------------------------------------
True Width Au Ag
Drill Hole From: To: (m) % Cu % Zn gm/mt gm/mt
----------------------------------------------------------------------
DB04B026 13 39 26 1.10 1.35 0.50 13.00
----------------------------------------------------------------------
65 69 4 0.50 1.39 3.00
----------------------------------------------------------------------
99 116 17 1.06 1.05 18.00
----------------------------------------------------------------------
129 144 15 0.30 0.06 6.00
----------------------------------------------------------------------
211 223 12 0.90 1.16 12.40
----------------------------------------------------------------------
255 266 11 0.50 0.82 8.20
----------------------------------------------------------------------
----------------------------------------------------------------------


Three hundred meters south, the Bismarck stope in the Bolivar mine hosts massive chalcopyrite-sphalerite mineralization that follows a fault and andesite dike plus disseminated chalcopyrite in massive calcite. The test stope was shut down because of grade too low for underground mining, but is within 40 meters of the surface and produced approximately 5000 m.t. of 0.68% Cu, 0.17% Zn, 0.48 gm Au/ m.t, 32.0 gm Ag/ m.t. while operating. Drilling encountered an additional 62 meters 0.87% Cu, 0.84% Zn, 0.1 gm Au/mt and 22.5 gm Ag/ mt 60 meters east of the stope. Sections through the Bismarck stope are open and mineralization continues in all directions. This zone is potentially open-pittable.

Two additional areas, Brecha Linda Surface and San Francisco Surface consist of fracture controlled and massive, chalcopyrite and sphalerite in andradite grossularite skarn that show strongly anomalous results from more than 500 surface samples (see Summary Results below) and produced significant drill intercepts in subsequent discovery drilling. Core hole DB09B281 drilled in these outcrops encountered a true width of 5.4 meters of 14.8 % Cu, 14.4% Zn, 0.6 gm Au/mt, and 330 gm Ag/mt.

Sample Summary Results (see Tables 2, 3, 4 and 5 in Disseminated Copper silver Progress Report)


----------------------------------------------------------------------------
----------------------------------------------------------------------------
Number Sample Data Cu Zn Au Ag
Area Samples type type % % gm/mt gm/mt Reference
----------------------------------------------------------------------------
Bolivar 2x2 &
Northwest 114 3x3 Panel Average 0.6 2.8 0.34 51 Table 2
----------------------------------------------------------------------------
Brecha Linda 100 2x2 Panel Average 0.3 0.7 0.1 14 Table 3
----------------------------------------------------------------------------
San Francisco
Sur Upper
Skarn 222 2x2 Panel Average 1.25 2.53 1.3 46 Table 4
----------------------------------------------------------------------------
San Francisco
Sur Lower
Skarn 88 2x2 Panel Average 0.8 0.0 0.7 32 Table 5
----------------------------------------------------------------------------
----------------------------------------------------------------------------


At San Francisco Sur, massive and disseminated chalcopyrite-bornite mineralization of the upper skarn crops out in garnet and pyroxene skarn. Mineralization extends east-southeast from the Pozo de Agua fault along the trace of host skarnitized carbonate and defines the southwest edge of the El Gallo area. Two hundred and twenty two rock chip samples collected from surface outcrops averaged 1.25% Cu, 2.53% Zn, 1.3 gm Au/mt, 46 gm Ag/mt (see Summary Table Above). Drill holes DB09B277 and DB09B278 drilled to test the skarn mineralization 10 meters down dip from surface outcrops encountered 11 meters of 0.71% Cu, 1.73% Zn, 0.3 gm Au/ m.t., and 56 gm Ag/ m.t. and 8.8 meters of 0.45% Cu, 1.85% Zn, 0.5 gm Au/ m.t., and 55 gm Ag/ m.t. respectively.

The southernmost of these mineralized areas, the El Gallo Upper Skarn, crops out on surface for approximately 400 meters. Here during the 2007 and 2008 drill program 20 holes penetrated disseminated and massive bornite, chalcopyrite, and sphalerite in andradite-grossularite skarn and so far have defined a small resource of 54,700 tons of 2.2 % copper, 4.7% zinc, 0.18 gm Au/ m.t., 47.5 gm Ag/ m.t. (See SGS Geostat calculations).

It is expected that the Bolivar copper-silver mineralization represents the first step toward the discovery of a copper porphyry skarn, as well as definition of low cost, open-pittable mill feed for Dia Bras' new on site mill.

Method of collection and analysis

All 2x2 and 3x3 meter chip panel samples were collected using single jacks and moils from painted panels then bagged and labeled as 3- to 5-kilogram sized samples. The samples averaged 3.8 kilogram in size and were sent by ALS Chemex Laboratories, Inc. ("ALS Chemex") transport to their Chihuahua, Mexico sample preparation facility.

Pulps were then sent by ALS Chemex of North Vancouver Assay Laboratory in Vancouver, BC, Canada for analysis. They were assayed for gold by 50 gram fire assay with AA finish and for silver by AA on 50 gram split sample. ALS Chemex analyzed the samples lead, zinc, and copper by Induction Coupled Plasma (ICP) and AA methods.

Quality control

The quality assurance-quality control (QA-QC) of Dia Bras and their contractors is as follows:

Samples are collected and handled only by Dia Bras authorized personnel, who collected them utilizing the methods described above. Samples were bagged and labeled with unique sample numbers on site then transported by Dia Bras personnel to the Dia Bras core handling facility and there stored for shipment. Weekly, ALS Chemex authorized personnel picked up and transported samples from Dia Bras core handling facility directly to their Chihuahua, Mexico sample prep facility. ALS Chemex Quality Assurance and Control procedures are described on their website at www.ALSchemex.com/mineral/quality. "Most ALS Chemex laboratories are registered or are pending registration to ISO 9001:2000 standards, and a number of analytical facilities have received ISO 17025 accreditations for specific laboratory procedures."

The technical content of this news release has been approved by Eugene K. Schmidt, RPG and Vice President of Exploration and Geology for Dia Bras, a Qualified Person as defined in NI 43-101.

To view the complete new discovery of disseminated copper-silver mineralization at Bolivar report please visit the link below: http://www.diabras.com/en/newscenter/2009/DIBPr15_DisseminatedCu_Ag_Bolivar_Report.pdf

To view the complete assay results for the Bolivar Northwest area, please visit the link below: http://www.diabras.com/en/newscenter/2009/DIBPr15_Table2.pdf

To view the complete assay results for the Breacha Linda area, please visit the link below: http://www.diabras.com/en/newscenter/2009/DIBPr15_Table3.pdf

To view the complete assay results for the San Francisco Sur area/upper skarn, please visit the link below: http://www.diabras.com/en/newscenter/2009/DIBPr15_Table4.pdf

To view the complete assays results for the San Francisco Sur area/lower skarn, please visit the link below: http://www.diabras.com/en/newscenter/2009/DIBPr15_Table5.pdf

About Dia Bras

Dia Bras is a Canadian exploration mining company focused on precious and base metals in the State of Chihuahua, in northern Mexico. The Corporation is committed to developing and adding value to its assets - the Bolivar copper-zinc project and the Cusi silver mining camp. The Corporation trades on the TSX Venture Exchange under the symbol "DIB".

Forward-looking statements

Except for statements of historical fact, all statements in this news release, without limitation regarding new project acquisitions future plans and objectives are forward-looking statements that 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 release.

Contact Information

  • Dia Bras Exploration
    Daniel Tellechea
    President & CEO
    514-393-8875
    or
    Dia Bras Exploration
    Eugene K. Schmidt
    Vice-President Exploration and Geology
    + (52) 614-426-0212