Dia Bras Continues to Discover High-Grade Silver With Gold By-Product Credits at its Cusi Property and Reports Mine Development Progress
TORONTO, ONTARIO -- (Marketwire) -- 05/17/11 -- Dia Bras Exploration Inc. (TSX VENTURE: DIB) ('Dia Bras' or the 'Company') is pleased to report that continued drilling in support of mine planning at its 100% owned, 11,319 hectare Cusi Property silver project has returned more significant exploration results. Dia Bras has received assays of high-grade silver intercepts from the Promontorio, Santa Eduwiges and San Juan mines, plus economically significant gold grades from San Juan. In addition, underground sampling at the San Juan mine has confirmed high grades of gold and silver. Both the Promontorio and San Juan mines are being prepared for pilot-mining during 2011.
'Significant areas of the historic San Juan mine are un-mined,' states Daniel Tellechea, President and CEO of Dia Bras. 'As mapping, sampling and drilling of the mine continue, our results demonstrate that the vein system could have major extent, and the presence of gold at San Juan is especially encouraging.'
A vein map of the Santa Eduwiges - San Juan area is shown in Figure 1 http://www.diabras.com/files/media/50d79_NR%20No%2017%20PR201105%20Figure%201.JPG. Locations of the San Juan drill holes reported here are shown in Figure 2 http://www.diabras.com/files/media/d648a_San%20Juan%20drill%20hole%20location%20map%20Figure%202.JPG. Sample results from Level 1 of the San Juan mine are shown in Figure 3 http://www.diabras.com/files/media/e2797_San%20Juan%20Level%201%20Sampling%20map%20Figure%203.JPG. The low lead and zinc assay results from the San Juan area indicate that this vein represents a high-level portion of the Cusi low-sulfidation, epithermal system, as compared to the Santa Eduwiges veins that often contain percent levels of lead and zinc. These assay results indicate that there is significant depth potential to the San Juan silver-rich vein.
Assay results from the three areas are shown in the following tables.
San Juan Area
Sampling of Level 1 of the San Juan mine has returned high grades of gold and silver. Complete results can be found on Figure 3 http://www.diabras.com/files/media/e2797_San%20Juan%20Level%201%20Sampling%20map%20Figure%203.JPG. The results from selected samples are shown in the table below.
Table 1. Sample Results from San Juan Vein at Level 1
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Sample # Width (m) Au g/t Ag g/t Pb % Zn %
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Vein Footwall
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379102 0.80 1.245 329 0.05 0.12
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379106 0.45 0.487 424 0.17 0.54
------------------------------------------------------------------------
379118 1.00 0.522 249 0.04 0.11
------------------------------------------------------------------------
379120 0.65 0.868 240 0.04 0.07
------------------------------------------------------------------------
379122 1.35 1.220 303 0.04 0.07
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Vein Hangingwall
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379103 0.85 0.673 145 0.05 0.11
------------------------------------------------------------------------
379105 0.80 0.459 233 0.03 0.08
------------------------------------------------------------------------
379107 0.70 1.700 436 0.08 0.10
------------------------------------------------------------------------
379109 0.70 0.725 558 0.15 0.37
------------------------------------------------------------------------
379117 0.60 0.423 221 0.11 0.12
------------------------------------------------------------------------
379121 0.65 1.295 388 0.10 0.14
------------------------------------------------------------------------
379142 0.75 0.697 343 0.06 0.06
------------------------------------------------------------------------
379143 0.65 9.340 1175 0.06 0.01
------------------------------------------------------------------------
The following table of drill results was published by the Company on February 24, 2011, but without all the gold values, as assays were pending for all but two samples. The gold assay values recently received are also shown in bold font in the table below.
Table 2. Recent and Previously Released Drill Assays from the San Juan Area
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Est.
True
From To Interval Width Au Ag Pb Zn
Hole ID(i) (m) (m) (m) (m) (g/t) (g/t) (% (%) Vein
----------------------------------------------------------------------------
San
297 96 96.25 3.25 1.19 1.96 1240 0.22 0.25 Juan
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302 44.80 46.00 1.20 0.78 0.38 185 0.01 0.03 '
----------------------------------------------------------------------------
and 49.55 53.00 3.45 2.23 0.55 314 0.04 0.06 '
----------------------------------------------------------------------------
306 183.0 186.00 3.00 0.52 0.17 165 3.20 3.20 '
----------------------------------------------------------------------------
309 65.00 65.55 0.55 0.29 0.37 574 0.23 0.08 '
----------------------------------------------------------------------------
311 71.20 77.20 6.00 2.09 0.85 174 0.03 0.03 '
----------------------------------------------------------------------------
326 79.30 81.10 1.80 0.42 0.23 169 0.27 0.22 '
----------------------------------------------------------------------------
327 117.40 119.30 1.90 0.48 0.26 197 0.54 0.09 '
----------------------------------------------------------------------------
329 72.15 76.00 3.85 1.72 0.20 153 0.02 0.07 '
----------------------------------------------------------------------------
333 52.60 53.60 1.00 0.58 0.68 166 0.03 0.08 '
----------------------------------------------------------------------------
334 77.75 82.85 5.10 1.84 0.61 311 0.38 0.41 '
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336 88.00 88.30 0.30 0.19 0.59 196 0.04 0.06 '
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and 95.25 108.00 12.80 4.61 0.47 151 0.04 0.06 '
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340 180.00 182.60 2.60 0.94 0.11 214 0.25 0.17 '
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344 86.05 87.20 1.15 0.41 0.22 172 0.02 0.04 '
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and 93.70 95.30 1.60 0.58 0.25 372 0.12 0.18 '
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(i) All holes have the prefix DC10B
The table below shows new assays from core drilling in the San Juan area.
Table 3. New Drill Assays from the San Juan Area
----------------------------------------------------------------------------
Est.
True
From To Interval Width Au Ag Pb Zn
Hole ID(i) (m) (m) (m) (m) (g/t) (g/t) (%) (%) Vein
----------------------------------------------------------------------------
San
325 142.0 143.1 1.1 0.77 AP 116 0.13 0.24 Juan
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and 145.2 146.2 1.0 0.70 AP 113 0.10 0.11 '
----------------------------------------------------------------------------
and 149.2 150.2 1.0 0.70 AP 113 0.10 0.21 '
----------------------------------------------------------------------------
304 77.5 81.0 3.50 2.45 0.46 98 0.04 0.03 '
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(i) prefix DC10B
AP - Assays Pending
Promontorio Area
Samples from the Promontorio and Santa Eduwiges mines are not assayed for gold because sufficient sampling has been done to demonstrate that the gold contents are low in those areas. The following table shows new assay results from the Promontorio area.
Table 4. New Drill Assays from the Promontorio Area
-----------------------------------------------------------------------
Est.
True
From To Interval Width Ag Pb Zn
Hole ID(i) (m) (m) (m) (m) (g/t) (%) (%) Vein
-----------------------------------------------------------------------
El
301 140.25 143.95 3.7 3.28 240 0.18 0.11 Gallo
-----------------------------------------------------------------------
328 191.2 191.50 0.3 0.2 101 0.31 0.53 '
-----------------------------------------------------------------------
(i) prefix DC10B
Santa Eduwiges Area
The following table shows assay results from drill samples at the Santa Eduwiges mine.
Table 5. New Drill Assays from the Santa Eduwiges Mine
-----------------------------------------------------------------------
Est.
True
From To Interval Width Ag Pb Zn
Hole ID (m) (m) (m) (m) (g/t) (%) (%) Vein
-----------------------------------------------------------------------
Sta.
Marina
305(i) 73.0 74.5 1.5 0.72 1195 0.11 0.13 Alto
-----------------------------------------------------------------------
and 82.30 83.75 1.45 0.60 215 0.03 0.07 '
-----------------------------------------------------------------------
307(i) 108.4 111.0 2.6 2.0 310 0.92 0.46 '
-----------------------------------------------------------------------
299(i) 33.17 35.80 2.63 1.90 201 0.08 0.20 '
-----------------------------------------------------------------------
Sta.
Marina
332(i) 381.2 381.5 0.3 0.2 368 2.08 2.19 Bajo
-----------------------------------------------------------------------
346(ii) 147.3 147.4 0.1 0.07 697 8.83 0.28 '
-----------------------------------------------------------------------
and 155.3 155.7 0.4 0.26 102 1.77 0.53 '
-----------------------------------------------------------------------
and 158.45 158.65 0.20 0.18 415 1.23 1.79 '
-----------------------------------------------------------------------
348(ii) 199.20 200.58 1.38 0.80 1690 8.56 10.90 '
-----------------------------------------------------------------------
and 200.58 202.00 1.42 1.20 4650 6.40 11.50 '
-----------------------------------------------------------------------
and 206.5 208.0 1.5 1.25 328 1.38 1.36 '
-----------------------------------------------------------------------
and 208.0 209.5 1.5 1.25 137 0.70 1.19 '
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(i) prefix DC10B
(ii) prefix DC11B
Mine Development
The following is some of the progress that has been made in developing the mines for pilot production during 2011:
-- Santa Eduwiges: Ramp development to access deeper portions of the
mineralized vein swarm in the area encountered between Levels 9 and 10 a
previously unknown old drift that measures about 300 m long. This drift
access is being rehabilitated and is expected to provide access to
deeper levels of the Tascates, Mexicana and Carta Blanca veins.
-- Promontorio: Construction of the hoist house and rehabilitation of the
electrical line have been completed, and the rock skip has been
installed. Cleaning of Level 9 is in progress in order to reach un-mined
portions of the Azucarera (known in English as the 'Sugar bowl') area of
the Veta del Contacto where historic mine records indicate
mineralization averaging 71 ounces per ton (2,201 grams per tonne)
silver were mined over an average width of one metre. Pumping is
maintaining the mine water level immediately below Level 9.
-- San Juan: The head frame is being raised in order to install a larger
skip, and a stronger winch cable. De-watering of the mine continues.
Cusi Production
2011 Cusi production as of May 13 (unaudited) was 8,963 tonnes of material with average grades of 213 g/t Ag, 1.43% Pb and 1.61% Zn, which was processed at the Company's Malpaso Mill. Recoveries from flotation were 68.32% for Ag, 67.97% for Pb and 23.72% for Zn.
Production of silver dore from the cyanidation vat leaching circuit is conducted periodically when the concentration of silver in the pregnant leach solution nears the saturation point. Through the end of April, an additional 25.82% Ag was recovered by cyanide vat leaching of the tails from flotation, producing 192.853 kg of silver dore, for a total flotation + cyanidation recovery of 82.10% for Ag (unaudited).
In addition, Management has decided to install a new agitation leach circuit at the Malpaso Mill to begin processing in 2011 of an estimated 75,000 tonnes of existing tailings at the Cusi Property grading up to 60 g/t Ag.
Method of Analysis
Samples were prepared at the ALS Chemex lab facility in Chihuahua, Mexico, and analyzed by ICP and AA methods at their facilities in Vancouver, Canada. Diamond drill samples sent for analysis consisted of half NQ-size and BQ-size diamond core split on site, prepared by the ALS Chemex sample preparation laboratory in Chihuahua, Mexico, and assayed for Au by 50 g fire assay with AA finish, and for Ag by AA on 50 g split sample at the ALS Chemex North Vancouver Laboratory. Assays for Pb, Zn and Cu are analyzed by Induction Coupled Plasma (ICP) at ALS Chemex.
Quality Control
The quality assurance-quality control (QA-QC) of 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, a Qualified Person as defined in NI 43-101.
About Dia Bras
Dia Bras is a Canadian exploration mining company focused on precious and base metals in Chihuahua State and other areas of northern Mexico. The Company is pursuing the development and exploration of its most advanced assets - the Bolivar Property (copper-zinc-silver) and the Cusi Property (silver). Dia Bras is also exploring several precious metal targets such as La Cascada project at the Bolivar Property, the Las Coloradas project at Melchor Ocampo (Zacatecas State), the Bacerac Property (Sonora State) and the Corralitos, Satevo and La Verde projects at the Batopilas Property (Chihuahua State).
The Company's shares trade on the TSX Venture Exchange under the symbol 'DIB'.
For further information on Dia Bras Exploration Inc. visit www.diabras.com.
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
Karl J. Boltz
Vice President, Corporate Development
Dia Bras Exploration Inc.
1 (866) 493-9646