Dia Bras Exploration Inc.
TSX VENTURE : DIB

Dia Bras Exploration Inc.

May 01, 2008 09:35 ET

Dia Bras: Initial NI 43-101 Resources Report on Cusi

2.12 Moz AgEq in the M+I category and 14.6 Moz AgEq in the Inferred category for Santa Edwiges and Promontorio

MONTREAL, QUEBEC--(Marketwire - May 1, 2008) - Dia Bras Exploration Inc. (TSX VENTURE:DIB) is pleased to report the first NI 43-101 compliant Mineral Resource Estimates for the Santa Edwiges and Promontorio sectors of its Cusi silver property, located in the State of Chihuahua, Mexico. The report concludes that work to date on these two sectors of interest has outlined resources as follows:

Measured and Indicated Category

As of March 31 2008, the Measured and Indicated Resources at the Santa Edwiges area stand at 131,000 tonnes at an average grade of 344 g/t AgEq (10.1 oz/t) for more than 1.45 Moz of silver equivalent and 103,000 tonnes at 201 g/t AgEq (5.9 oz/t) for 587,550 ounces of silver equivalent at Promontorio area. The combined resources are contained within 234,000 tonnes at an average grade of 284 g/t AgEq for about 2.12 Moz AgEq. Pure silver amounts to approximately 1.4 M oz, for a Ag - AgEq ratio of 65%.

Inferred Category

The Inferred Resources for both areas are 1.39 million tonnes grading 0.24 g/t Au and 188 g/t Ag (326 g/t silver-equivalent) at a cut off grade of 120 g/t silver-equivalent. The Inferred Resource at Santa Edwiges stands at 936,000 tonnes at an average grade of 333 g/t AgEq (9.65 oz/t) for about 10.02 Moz of silver equivalent as well as 458,000 tonnes at an average grade of 312 g/t AgEq (9.22 oz/t) for some 4.59 Moz of silver equivalent at Promontorio.

Silver equivalent for both categories was calculated using the formula: AgEq equals Ag+70.1 X Au+62.2 X Zn+43.3 X Pb

Daniel Tellechea, President & CEO of Dia Bras states, "We are very pleased with the results of the initial resources estimate at Cusi. The M+I resources indicate a potential for approximately 2 years of small scale mining of approximately 300 tons per day while more resources are being added to our resources base at Cusi, thus allowing us to achieve our 2008 target of pilot mining for Cusi ."

Francois Auclair, Vice-President, Exploration adds, "The Exploration potential remains huge because only 10 km2 of the Cusi property has been explored by modern mining exploration techniques. More importantly, only two of the twelve historical producers have been targeted, with over 5,000 metres of continuous drilling. Furthermore, both Santa Edwiges and Promontorio demonstrate potential for more resources along strike and down dip."

Geostat has estimated the Mineral Resources of the Cusi project using the database up to March 31, 2008, which includes 202 diamond drill holes (surface and underground) for a total of 9201 sampled intervals. The resource estimate was calculated using 92 mineral intersections (within the 202 drill holes). The database used by Dia Bras was provided to Geostat and was incorporated in Geostat software.

Most of the Resources were calculated by an inverse square distance block model, the remainder by cross sectional method.

The mineralization at Promontorio is associated with fracture-filled, low-sulphidation veins with high precious-metals grades, typical of a high level epithermal system. The most prominent vein in the sector is Veta A, and Dia Bras has reported high historical grades as well as the Company's drill core data from this vein and from its intersections with cross cutting subsidiary veins (see press release June 7, 2007).

The Santa Edwiges--San Antonio--San Marina sector consists of multiple fracture-filled quartz-carbonate veins containing high sulphide contents that are typical of the middle portion (Pb, Zn, Cu) of a zoned, epithermal vein system. This middle portion of the veins transitions upwards to the upper precious metal (Au, Ag) portion of the veins.

The Mineral Resources of the Cusi project have been calculated for only two areas of the Cusi camp, Santa Edwiges (including Santa Marina) and Promontorio. More resources will be added to this initial estimate when resources from the La Bamba - San Miguel option and other areas of the Cusi camp are added to these first calculations.



Resources - Total of Promontorio and Santa Edwiges
Calculated by Yann Camus, Eng., Geostat Systems International Inc.,
Resources situation on the 2008-03-31 Cutoff at 120 g/t AgEq, 2m minimum
horizontal width for structures, density of 2.7

---------------------------------------------------------------------------
AgEq
Classifi- Au Ag Cu Pb Zn (i) Onces of Onces of
cation Tonnes (g/t) (g/t) (%) (%) (%) (g/t) Ag AgEq
---------------------------------------------------------------------------
Measured 11,000 0.05 207 0.04 0.47 0.51 263 76,380 96,650
---------------------------------------------------------------------------
Indicated 223,000 0.12 186 0.05 0.81 0.84 282 1,336,870 2,024,500
---------------------------------------------------------------------------
Measured
+Indicated 234,000 0.12 187 0.05 0.80 0.82 281 1,413,260 2,121,160
---------------------------------------------------------------------------
Inferred 1,394,000 0.24 188 0.06 1.15 1.14 326 8,434,810 14,614,410
---------------------------------------------------------------------------
(i): Silver Equivalent AgEq equals Ag+70.1 X Au+62.2 X Zn+43.3 X Pb

Resources - Santa Edwiges - All Structures
Calculated by Yann Camus, Eng., Geostat Systems International Inc.,
Resources situation on the 2008-03-31 Cutoff at 120 g/t AgEq, 2m minimum
horizontal width for structures, density of 2.7

---------------------------------------------------------------------------
AgEq
Classifi- Au Ag Cu Pb Zn (i) Onces of Onces of
cation Tonnes (g/t) (g/t) (%) (%) (%) (g/t) Ag AgEq
---------------------------------------------------------------------------
Measured 9,000 0.03 205 0.05 0.52 0.58 266 59,590 77,200
---------------------------------------------------------------------------
Indicated 122,000 0.15 195 0.07 1.34 1.39 350 766,110 1,376,490
---------------------------------------------------------------------------
Measured
+Indicated 131,000 0.14 196 0.07 1.28 1.34 344 825,710 1,453,700
---------------------------------------------------------------------------
Inferred 936,000 0.32 144 0.06 1.58 1.58 333 4,343,280 10,021,390
---------------------------------------------------------------------------
(i): Silver Equivalent AgEq equals Ag+70.1 X Au+62.2 X Zn+43.3 X Pb

The Projection of the Mineralized zones of the Santa Edwiges Sector is
available at the following address:
http://media3.marketwire.com/docs/DIB_Santa_Edwiges.jpg

Resources - Promontorio - All Structures
Calculated by Yann Camus, Eng., Geostat Systems International Inc.,
Resources situation on the 2008-03-31 Cutoff at 120 g/t AgEq, 2m minimum
horizontal width for structures, density of 2.7

---------------------------------------------------------------------------
AgEq
Classifi- Au Ag Cu Pb Zn (i) Onces of Onces of
cation Tonnes (g/t) (g/t) (%) (%) (%) (g/t) Ag AgEq
---------------------------------------------------------------------------
Measured 2,000 0.18 215 0.03 0.24 0.17 249 16,790 19,450
---------------------------------------------------------------------------
Indicated 101,000 0.08 176 0.03 0.18 0.17 200 570,760 648,010
---------------------------------------------------------------------------
Measured
+Indicated 103,000 0.08 177 0.03 0.18 0.17 201 587,550 667,460
---------------------------------------------------------------------------
Inferred 458,000 0.08 278 0.05 0.29 0.25 312 4,091,530 4,593,020
---------------------------------------------------------------------------

(i): Silver Equivalent AgEq equals Ag+70.1 X Au+62.2 X Zn+43.3 X Pb

The Projection of the Mineralized zones of the Promontorio Sector is
available at the following address:
http://media3.marketwire.com/docs/DIB-Promontorio.jpg


Notes:

1. CIM Definitions were followed for the resource estimate.

2. A minimum width of 2 m was used for a mineralized zone.

3. Densities of mineralized rock are indicated in the tables.

4. Equivalent Ag grades and contained ounces were estimated based on gold, silver, lead, and zinc plant recoveries as per the most recent metallurgical test work and smelter terms.

5. Mineral resources that are not mineral reserves do not have demonstrated economic viability

6. Price assumptions used for the AgEq calculation (US$): Ag 11.00/oz, Au 600.00/oz, Cu 2.00/lb, Zn 1.00/lb, Pb 0.65/lb.

The NI 43-101 Resources were prepared by Yann Camus, P Eng., Geo and Maxime Dupere, P Geo, of Geostat Systems International as at April 28, 2008, both Independent Qualified Persons as per NI 43-101 definition.

A complete technical report will be available under Dia Bras Exploration on the SEDAR website at www.sedar.com and on Dia Bras' website at www.diabras.com within 45 days of the present.

Metallurgical Study

Batch test samples have been sent to San Luis Potosi University for metallurgical testing. The study is headed by Dr Alejandro Lopez Valdivieso (PhD Minerals Engineering, UC Berkeley and M.Sc.A. Metallurgy, South Dakota School of Mines) and Mr. Ruben Tello Flores, Metallurgist.

This program was initiated for Santa Edwiges and includes mineralogical studies and flotation tests to obtain both a silver-lead concentrate and a zinc concentrate. The first results from the flotation tests are very promising. They indicate that it is feasible to produce a lead concentrate with 60% Pb and 1 kg / ton Ag with a recovery of 75% for lead and 70% for silver and also to produce a zinc concentrate with 55% Zn with low levels of lead and iron for a zinc recovery of 70%. This metallurgical study is continuing to improve recoveries for silver, lead and zinc.

In respect to Promontorio, metallurgical testing is in process to obtain silver concentrate.

Exploration Potential

The Company's current drilling program of 15,000 m of diamond drilling is being conducted on the northwestern portion of the project where 12 inactive silver mines are located. As of April 30, more than 8,000 m of core diamond drilling has been completed. The objective of the drilling is to test the down-dip and strike extensions of the silver veins in the Santa Edwiges and Promontorio mines as well as define new mineralize structures previously untested.

The reconnaissance mapping and prospecting of the La Reina sector of the Cusi property was conducted in February and March and results from the sampling program are awaited. A 2,000 metres drilling program will target the most prospective zones define during the prospecting program.

The technical content of this news release has been approved by Francois Auclair, P. Geo. and Vice-President, Exploration of Dia Bras, a Qualified Person as defined in NI43-101.

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 Company is committed to developing and adding value to its assets - the Bolivar copper-zinc project and the Cusi silver mining camp as well as the newly option La Enganosa property situated in Jalisco state. The Company 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 projects, 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.

Contact Information

  • Dia Bras Exploration
    Daniel Tellechea
    President & CEO
    514-393-8875 ext. 241
    or
    Dia Bras Exploration
    Francois Auclair
    Vice-President, Exploration
    514-393-8875 ext. 243
    www.diabras.com