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Press release from PR Newswire

Dia Bras Drilling Programme continues to expand and clarify the silver disseminated mineralisation at its Promontorio mine (Cusi Property) and is discovering structures inside the disseminated zone with High Silver Grades

Tuesday, July 17, 2012

Dia Bras Drilling Programme continues to expand and clarify the silver disseminated mineralisation at its Promontorio mine (Cusi Property) and is discovering structures inside the disseminated zone with High Silver Grades11:32 EDT Tuesday, July 17, 2012 TSX Venture Exchange - DIB # 24-2012 TORONTO, July 17, 2012 /PRNewswire/ - Dia Bras Exploration Inc. (TSX-V:DIB) ("Dia Bras" or the "Company") is pleased to report that continued drilling from  surface at its Promontorio mine has expanded the wide zones of disseminated silver mineralization at the Promontorio mine. The extent of the disseminated mineralized zone is becoming clearer and illustrates the significant potential of this discovery. Press Release Highlights: The Company's geologists infer that the disseminated zone could extend over an area of at least 150 m x 200-300 m, indicating major volume potential. Drill hole DC12B476 at the Promontorio mine cut 8.3 m averaging 1,296 g/t Ag within a 23 m zone averaging 543 g/t Ag within a second-order vein in the disseminated zone. DC07B151 drilled in 2007 cut the same vein 250 m below the surface with 15 m averaging 528 g/t Ag, demonstrating the down-dip continuity of this high-grade structure inside the disseminated zone. Since the disseminated zone was recognized, the Company has completed 47 surface and 12 underground drill holes in the zone and has conducted rehabilitation of the Promontorio shaft and historical underground workings.  During the period January-June, the Company completed 15,129 m of diamond drilling, 619 m of underground drilling at Promontorio mine and 14,510 m of surface drilling on four targets. "As our drilling and development continue, we are especially excited about the tremendous upside potential of the Promontorio disseminated zone," stated Daniel Tellechea, President and CEO of Dia Bras Exploration.  "The remarkably high grades in structures inside the disseminated zone and the larger, overall size of the zone, prove that our recent strategy of a more aggressive exploration and development program for our Cusi silver property is yielding positive surprises and is proving to have been the right strategy to add shareholder value through organic growth.  We are rehabilitating the old workings in this area and developing new drill stations that will allow us to drill at tighter spacing and determine our development and mine plan for this important discovery.  This discovery is significant to Dia Bras because it is in an historic mine with underground infrastructure near the areas of disseminated mineralization. The Company will continue its pilot-mining operations at Cusi and plans to release a NI 43-101 resource report in late 2012 or early 2013." Promontorio Disseminated Zone: The Promontorio disseminated zone was first recognized in late summer, 2011 (see press release of September 14, 2011).  Since then, the Company has completed 47 surface and 12 underground drill holes in the zone (totaling 9875.5 m and 607.2 m, respectively) and has conducted rehabilitation of the Promontorio shaft and historical underground workings.  Development continues, especially the extension of the ramp from Level 4 with the objective of providing access to the zone for pilot mining and for constructing drill stations that are better positioned to define the zone. The disseminated zone is bounded by the Cusi Fault and occurs in and around the Promontorio Main Vein and several of its subsidiary veins, such as veins J and L, which have strike lengths of hundreds of meters.  These veins strike more or less NE and truncate against the NW-trending Cusi Fault (see Figure 1).  It is now recognized that between these veins are second-order veins that strike generally E-W but have short strike lengths, on the order of less than 25 m up to100 m.  These veins are distributed in a relatively random pattern.  These second-order veins and the mm-scale fractures that are more or less parallel to them provided the fluid pathways for the mineralizing hydrothermal fluids that created the disseminated zone.  As a result of the random nature of the second-order veins, interpreting their drill intercepts is difficult because a vein may only show up on a single section and pinch out before it reaches the next section 25 m away. Figure 2 is a cross section showing one of these second-order veins and its envelope of disseminated mineralization.  Drilling has identified other second-order veins of short strike length, which are shown on Figure 3. The vein in Figure 2 has a short strike length (not defined but probably about 100 m) but varies in width from 10 to 20 m.  The vein has been drilled to a depth of 250 m below the surface and is open to depth.  More holes at a tight spacing are required to define this vein.  It is worth repeating that drill hole DC12B476 cut this second-order vein in the disseminated zone and averaged 1,296 g/t Ag over 8.3 m within 23 m interval averaging 543 g/t Ag. Figure 3 is a plan view of Level 8 of the Promontorio Mine that shows the known limit of the disseminated zone at its southwestern edge and where it is open to the northeast towards and along the Cusi Fault.  The vein of Figure 2 can be seen on Figure 3, within the disseminated zone. Although significant drilling remains to be done to determine the limits of the disseminated zone towards the Cusi Fault and to the NW and SE, the Company's geologists believe the volume potential of this zone is large.  As shown in Figure 3, the zone has a minimum width of approximately 100 m and is open towards and along the Cusi Fault, an observation that supports the interpretation by the Company's geologists that the zone could extend NW-SE for 200-300 m.  Drilling has already shown that the zone extends vertically at least 250 m.  Because of the zone's potential size, many holes will have to be drilled to define it.  Drill stations planned along the ramp from Level 4 will provide better positions for drilling. Drilling Results Significant results from surface and underground drill holes at Promontorio are presented in Tables 1 & 2, from El Gallo in Table 3, and from Santa Eduwiges in Table 4. Table 1: Summary of Promontorio Surface Drill Results Hole Number*   From (m)   To (m)   Core Length (m)   Est. True Width (m)   Au g/t   Ag g/t   Pb %   Zn %   Mn % DC07B151   181.5   196.5   15.0   12.4   nd**   528   0.27   0.21   1.16 428   63.0   93.0   30.0       0.005   63   0.05   0.06   0.76 432   75.0   78.2   3.2       0.023   622   0.66   0.67   0.44 455   93.75   94.45   0.7   0.7   0.169   1,720   0.01   0.02   0.03 465   126.50   132.85   6.35   3.2   0.030   535   0.32   1.12   0.24 and   157.4   161.6   4.2   2.1   0.005   65   0.12   0.10   0.15 and   167.3   216.45   49.15   31.6   0.037   98   0.23   0.26   0.66 and   318.2   329.2   11.0   7.0   0.143   118   0.28   0.41   0.47 470   187.5   201.7   14.2   10.9   0.089   187   0.19   0.32   0.27 472   204.0   219.6   15.6   14.3   0.062   215   0.45   0.49   0.95 and   298.9   303.7   4.8   4.5   0.093   150   1.17   1.96   0.83 476   142.1   165.0   22.9   21.0   0.067   543   0.15   0.13   0.89 incl.   143.9   152.2   8.3   7.6   0.150   1,296   0.27   0.21   1.33 482   255.1   270.2   15.1   11.2   0.131   73   0.76   0.74   0.28 484   118.4   139.1   20.7   19.4   0.023   94   0.09   0.11   0.84 485   124.4   128.7   4.3   3.5   0.052   76   0.75   0.52   0.28 and   135.5   143.5   8.0   5.0   0.059   82   0.40   1.32   0.42 488   121.5   123.8   2.3       0.029   124   0.13   0.12   0.40 and   133.7   146.6   12.9   9.1   0.027   63   0.09   0.09   0.10 492   188.6   224.5   35.9   17.0   0.048   101   0.44   0.42   0.92 493   122.1   124.9   2.8       0.079   335   0.78   0.77   0.03 and   135.4   136.6   1.2       0.080   1,120   0.21   0.51   0.04 497   177.6   184.1   6.5       0.009   94   0.12   0.17   0.77 and   199.4   203.7   4.3       0.012   50   0.09   0.10   0.43 and   216.1   221.0   4.9       0.175   162   1.79   1.11   0.36 and   253.8   266.7   12.9       0.087   53   0.17   0.41   0.33 * All holes have prefix DC12B except DC07B151 (results published January 30, 2008) ** nd = not determined Table 2: Summary of Promontorio Underground Drill Results Hole Number*   From (m)   To (m)   Core Length (m)   Est. True Width (m)   Au g/t   Ag g/t   Pb %   Zn %   Mn % 111   19.9   23.5   3.6       0.033   340   0.75   0.59   1.31 and   58.5   69.5   11.0       0.041   136   0.05   0.08   1.07 and   72.0   75.0   3.0       nd**   78   0.07   0.03   0.01 113   9.0   11.4   2.4       nd   124   0.08   0.25   2.94 and   23.4   25.8   2.4       0.026   209   0.20   0.23   0.83 114   30.0   32.4   2.4       nd   445   0.35   0.49   2.02 115   11.2   13.1   1.9       0.032   132   0.16   0.29   1.45 117   33.0   36.0   3.0       nd   112   0.07   0.06   0.17 118   28.5   40.5   12.0       nd   60   0.04   0.08   0.38 * All holes have prefix DC12M ** nd = not determined Table 3: Summary of El Gallo Surface Drill Results Hole Number*   From (m)   To (m)   Core Length (m)   Est. True Width (m)   Au g/t   Ag g/t   Pb %   Zn %   Mn % 445   3.55   13.85   10.3   7.9   0.083   186   0.14   0.03   0.07 and   68.85   71.50   2.65   0.9   0.334   330   0.18   0.92   0.03 447   10.2   19.1   8.9   2.5   0.094   211   0.11   0.05   0.04 and   60.6   63.0   2.4   1.2   0.075   116   0.10   0.09   0.02 and   75.0   78.0   3.0   2.3   0.105   123   0.04   0.15   0.08 467   35.2   41.1   5.9       0.021   72   0.02   0.02   0.02 and   50.3   51.4   1.1       0.747   766   0.31   0.09   0.02 and   74.3   76.1   1.8       0.010   222   0.03   0.12   0.09 and   98.3   99.1   0.8       0.168   955   0.12   0.11   0.05 473   61.5   64.5   3.0       0.025   113   0.07   0.11   1.41 and   93.0   99.0   6.0       0.012   105   0.04   0.07   0.84 * All holes have prefix DC12B Table 4: Summary of Santa Eduwiges Surface Drill Results Hole Number*   From (m)   To (m)   Core Length (m)   Est. True Width (m)   Au g/t   Ag g/t   Pb %   Zn %   Mn % 441   143.05   156.75   13.7   8.0   0.057   126   0.66   0.43   0.23 and   171.9   173.0   1.1   0.8   0.206   129   0.18   0.24   0.59 and   188.05   196.7   8.65   6.6   0.695   345   1.47   0.95   0.65 and   198.0   199.0   1.0   0.6   1.500   477   0.76   0.65   0.44 444   178.40   181.65   3.25       0.115   114   0.69   0.89   0.14 446   133.2   136.2   3.0   1.5   0.839   258   0.21   0.13   0.39 and   148.7   151.7   3.0   2.1   0.665   278   0.30   0.26   1.09 448   186.0   198.6   12.6   8.0   0.196   161   1.83   1.52   0.34 454   103.75   115.00   11.25       0.037   55   0.17   0.30   0.32 466   89.4   93.5   4.1       0.023   67   0.24   0.27   0.95 468   173.3   174.0   0.7       0.155   1,215   10.05   19.70   0.71 and   379.5   380.7   1.2       0.163   771   0.14   0.26   0.58 477   121.25   130.40   9.15   4.0   0.093   78   0.32   0.58   0.66 and   137.2   141.5   4.3   2.5   0.435   352   7.25   1.45   1.44 479   77.3   78.7   1.4   0.6   0.178   239   3.51   5.39   0.49 and   126.9   128.2   1.3   1.0   0.025   215   1.58   4.32   0.28 and   141.0   142.5   1.5   0.5   0.045   137   2.03   5.35   0.10 and   157.8   172.8   15.0   8.5   0.022   83   0.35   0.75   0.19 486   57.9   58.5   0.6       1.957   2,297   0.07   0.11   0.80 and   109.0   109.5   0.5   0.3   0.102   1,370   0.66   1.20   0.67 and   149.7   152.2   2.5   1.5   0.251   140   0.20   0.05   0.95 * All holes have prefix DC12B Cusi Pilot Mining Update:     During June, the Company's wholly-owned Malpaso mill processed 4,641 tonnes of development rock averaging 204.4 g/t Ag.  Pilot mining provides important information on metallurgy, recovery rates, mining and milling costs, etc., that are essential in determining the economic viability of a project. Development of the Promontorio and Santa Eduwiges mines continues.  During the month of June, development at Santa Eduwiges was done on Levels 7.5, 8.5 & 10, three stopes were started, and Ramp 9384 SW was advanced 46 m at -12% from Level 10 towards Level 11. At Promontorio, a contractor was engaged to extend the ramp from Level 4 to Level 9 and to clean and rehabilitate the Promontorio shaft from Level 9 to Level 11. The table below shows the results from sampling of veins along the development drifts: Mine Level Heading Length Sampled (m) Avg. Vein Width (m) Ag g/t Pb % Zn % Promontorio 9 Fte 986 SW 18.0 5.0 152 0.19 0.22 Santa Eduwiges 7 Fte 256 SE 20.0 1.81 181 2.70 5.27 " 7.5 Fte 604 SW 22.0 1.30 329 1.12 0.98 " 7.5 Fte 440 NE 23.0 0.97 380 pending pending " 8.5 Fte 420 NE 23.0 1.08 552 0.40 0.55 " 8.5 Reb 672 SW 25.0 1.14 478 1.44 2.23 " 8.5 Fte 9375 SW 13.0 1.35 267 0.99 0.61 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 Qualified Person as defined in NI 43-101. About Dia Bras Dia Bras Exploration is a Canadian mining company focused on precious and base metals in Chihuahua State, other areas of northern Mexico, and most recently at its Yauricocha silver-lead-zinc-copper-gold mine in Peru. The Company is accelerating exploration at the Yauricocha property as well as pursuing the development and exploration of its most advanced Mexican assets - the Bolivar Property (copper-zinc-silver) and the Cusi Property (silver-lead) and is exploring in Mexico several precious metal targets such as La Sidra gold project at the Bolivar Property, Las Coloradas silver project at Melchor Ocampo (Zacatecas State), the Bacerac silver project (Sonora State), and the La Verde gold project at the Batopilas Property (Chihuahua State).  Dia Bras is also exploring base metal projects in Mexico such as the Corralitos intrusion-hosted molybdenum deposit (Chihuahua State). The Company's shares trade on the TSX Venture Exchange under the symbol "DIB".  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. 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.    SOURCE Dia Bras Exploration Inc.Image with caption: "Figure 1: Cusi Project Map View (CNW Group/Dia Bras Exploration Inc.)". Image available at: http://photos.newswire.ca/images/download/20120717_C8801_PHOTO_EN_16272.jpgImage with caption: "Figure 2: Cross Section Showing Second-Order Vein in Disseminated Zone and its envelope of disseminated silver mineralization. (CNW Group/Dia Bras Exploration Inc.)". Image available at: http://photos.newswire.ca/images/download/20120717_C8801_PHOTO_EN_16271.jpgImage with caption: "Figure 3: Map of Level 8 showing vein of Figure 2, other second-order veins and contours of silver content.  Disseminated zone closed off to SW but open elsewhere. (CNW Group/Dia Bras Exploration Inc.)". Image available at: http://photos.newswire.ca/images/download/20120717_C8801_PHOTO_EN_16270.jpgFor further information: <p> For further information on Dia Bras Exploration Inc. visit <a href="http://www.diabras.com">www.diabras.com</a> or contact: </p> <p> <b>Daniel Tellechea</b><br/> <b>President & CEO </b><br/> Dia Bras Exploration Inc.<br/> 1 (866) 493-9646<br/> <br/> <b>Matt Morrish</b><br/> <b>Director, Investor Relations</b><br/> Dia Bras Exploration Inc.<br/> 1 (866) 493-9646<br/> </p>