Dia Bras Exploration Inc.
TSX VENTURE : DIB

Dia Bras Exploration Inc.

November 12, 2007 12:46 ET

Dia Bras Receives Positive Results From Preliminary Economic Assessment on the Bolivar Cu-Zn deposit

MONTREAL, QUEBEC--(Marketwire - Nov. 12, 2007) - Dia Bras Exploration (TSX VENTURE:DIB) is pleased to announce positive results from the preliminary economic assessment of the Bolivar deposit technical report. The report, dated November 9th, 2007, was conducted by Yann Camus, Eng., from Geostat International, independent Qualified Person under NI 43-101 standards. The complete report has been filed on SEDAR and posted on Dia Bras' website.

The results of this 43-101 compliant resource evaluation conducted by Geostat was announced on September 25th 2007 and indicated that the Upper Skarn Unit contains some 322,400 tonnes at 5.16% Cueq in the measured and indicated categories and 274,600 tonnes at 5.67% Cueq in the inferred category at a cut off grade of 2.5% Cueq. Further, at various cut-off grades, the Lower Skarn Unit contains from 936,000 tonnes at 1.99 % Cueq (1.5% Cueq cut-off) up to 3,248,000 Mt at 1.34% Cueq (0.75% Cueq cut-off) (Cueq includes Cu, Zn, Au and Ag; see Press Release of September 25th).

These results guided the preliminary economic assessment study, with the objective of building a mill on site at the Bolivar deposit. This would optimize the mine resources by reducing direct costs related to production and transportation of ore. The current operation utilizes the Malpaso mill, which is located 300 km from the mine.

Although inferred resources are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves, as part of a preliminary assessment, and for the economic part of this preliminary assessment, inferred resources can be included. Some mining dilution has been added. However, and due to the preliminary nature of the report, there is no certainty that the preliminary assessment will be realized. Mineral resources that are not mineral reserves do not have demonstrated economic viability.

Two economic scenarios were examined. The first scenario is to mine 1,248,000 tonnes at 3.28% Cueq fully diluted. The Malpaso Mill is used during the first two years while a 500 tonnes per day maximum capacity mill is installed near the mine site for the remaining years. The second scenario is to mine 2,035,000 tonnes at 2.53% Cueq fully diluted. The Malpaso Mill is also used during the first two years and a 1,000 tonnes per day maximum capacity mill is installed near the mine site for the remaining years.

Both scenarios prove economically viable with undiscounted NPVs of $34,293,000 for the first scenario and $29,104,000 for the second scenario. NPVs at a 10% discount are $21,102,000 for the first scenario and $15,443,000 for the second scenario. Geostat's recommendation is to proceed with a pre-feasibility study.

The estimated price for copper in the cash flows is $3.00 for the first year, $2.50 for the second year and $2.00 for the next six (6) years. For the other metals, price assumptions vary in the same proportions with first year at US$1.50/lb. for Zn, US$15.00/oz Ag, and US$750/oz Au, second year at US$1.25/lb. for Zn, US$12.50/oz Ag, and US$625/oz Au and the next six years at US$1.00/lb. for Zn, US$10.00/oz Ag, and US$500/oz Au. Further, in the economic study the overall mill recovery is established at 90%. After construction of the new mill at Bolivar, the Malpaso mill would be used to process rock from the Company's silver deposits at Cusi.

"The positive results of the preliminary economic assessment study are very encouraging and dictate that we should pursue our work and proceed with a feasibility study" said President and CEO Daniel Tellechea. "Further, the ongoing exploration program will allow us to rapidly increase our confidence level in the resource and build a larger and richer resource base at Bolivar. The exceptional drill intersections in both the El Gallo and the El Val areas allow Dia Bras to estimate that more resources will be added to this current base case scenario."

At the moment, 4 diamond drill rigs and 2 underground diamond drill rigs are active at Bolivar, with the objective of defining Inferred Resources of the Upper and Lower Skarn and try to confirm these as Measured or Indicated resources. This would increase the resource base to allow for a longer mine life and an increase of the mining volume.

In the El Val area, one drill rig is drilling on trend to the northwest of the newly drilled mineralized zone of the La Narizona showing, while another drill rig is updating the resource base at El Gallo, where significant Lower Skarn mineralization has been outlined over less than 5% of the known mineralized area.

A map of the Bolivar Mine Area is available at the following address: http://www.ccnmatthews.com/docs/Dia_Bras_Map.pdf

The Mineral Resources of the Bolivar Deposit are summarized in the following tables:



Table 1

------------------------------------------------------------------------
Resources of the Upper Skarn of the Bolivar Project
Calculated by Yann Camus, Geostat Systems International Inc., 2007-09-22
The cut-off grade applied in the Upper Skarn is 2.5% Cueq
------------------------------------------------------------------------
------------------------------------------------------------------------
Mineralized SG Cu Zn Au Ag % %
Classification Areas Tonnes (t/m3) % % (g/t) (g/t) Fe Cueq(i)
------------------------------------------------------------------------
------------------------------------------------------------------------
Total Measured All areas 85,900 3.52 1.75 7.01 0.11 25.7 6.04 5.46
------------------------------------------------------------------------
Total Indicated All areas 236,400 3.52 1.84 5.63 0.30 45.2 6.58 5.05
------------------------------------------------------------------------
Measured+
Indicated All areas 322,400 3.52 1.82 6.00 0.25 40.0 6.44 5.16
------------------------------------------------------------------------
Total Inferred All areas 274,600 3.52 2.04 6.36 0.35 50.5 6.73 5.67
------------------------------------------------------------------------


In addition to the resources of the Upper Skarn, inferred resources have been calculated for the Lower Skarn in the El Gallo area. Table 2 shows the inferred tonnage at various %Cu-eq cut-off grades:



Table 2

------------------------------------------------------------------------
Resources of the Lower Skarn of the Bolivar Project
The cut-off grade applied in the Lower Skarn (%Cueq) is variable
------------------------------------------------------------------------
------------------------------------------------------------------------
Cutoff
on the SG % % Au Ag % %
%Cueq Classification Tonnes (t/m3) Cu Zn (g/t) (g/t) Fe Cueq(i)
------------------------------------------------------------------------
------------------------------------------------------------------------
0.50 Inferred 6,114,000 3.27 0.76 0.13 0.20 15.1 12.50 0.99
------------------------------------------------------------------------
0.75 Inferred 3,248,000 3.27 1.04 0.14 0.27 20.5 15.26 1.34
------------------------------------------------------------------------
1.00 Inferred 2,320,000 3.27 1.19 0.15 0.31 23.2 16.79 1.52
------------------------------------------------------------------------
1.25 Inferred 1,438,000 3.27 1.39 0.17 0.38 26.4 18.43 1.77
------------------------------------------------------------------------
1.50 Inferred 936,000 3.27 1.57 0.17 0.45 29.3 19.22 1.99
------------------------------------------------------------------------

Notes:
1. CIM Definitions were followed for the resource estimate.
2. A minimum width of 2 m was used for a mineralized zone.
3. Cueq are based on recovered grade at the Malpaso Mill.
4. Densities of mineralized rock are indicated in the tables.


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 and Yann Camus, Eng., from Geostat International, independent Qualified Person under NI 43-101 standards.

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. 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.

The TSX Venture Exchange does not accept responsibility for the adequacy or accuracy of this press release.

Contact Information

  • Dia Bras Exploration
    Thomas L. Robyn
    Executive Chairman
    514-393-8875
    or
    Dia Bras Exploration
    Daniel Tellechea
    President & CEO
    514-393-8875
    www.diabras.com
    or
    Sun International Communications
    Nicole Blanchard
    Managing Partner
    450-627-6600