Dia Bras expands silver mineralization at the Promontorio and Santa Eduwiges mines, Cusi Property
TSX Venture Exchange - DIB
Bolsa de Valores de Lima - DIB
TORONTO, May 14, 2012 /PRNewswire/ - Dia Bras Exploration Inc. (TSX-V:DIB) ("Dia Bras" or the "Company") is pleased to report that continued surface and underground drilling at its Promontorio mine (Figure 1: Cusi Project Map View) has expanded the Promontorio disseminated silver deposit and the El Gallo veins while development work on Level 9 of Promontorio mine has encountered good grades of silver in the disseminated zone. Additionally, drilling at Santa Eduwiges has cut several new zones of high grade silver mineralization.
Press Release Highlights:
"These and previous results demonstrate the exceptional silver exploration potential of the Cusi property." stated Daniel Tellechea, President and CEO of Dia Bras Exploration. "These results provide the basis to accelerate our exploration program with the objective of defining additional resources for the future and commissioning an updated 43-101 compliant resource at the end of this year."
The Company has completed thirteen new drill holes in the past six weeks. These holes are part of the Company's continuing program directed at expanding the resources of the Cusi property and providing data for mine planning for the pilot mining program.
Significant results from the thirteen holes are presented in "Table 1: Summary of Cusi Drill Results", below:
Table 1: Summary of Cusi Drill Results
|Hole Number||From (m)||To (m)||
|Au g/t||Ag g/t||Pb %||Zn %||Mn %||Vein|
* Underground hole drilled from Level 5 of Promontorio mine
** nd = not determined
Significance of Results:
Promontorio Mine: As shown in Figure 2, drill hole DC12M108 intercepted disseminated silver mineralization on Level 5, which is about 40 m above the previous intercept between Levels 6 & 7. This result shows that the disseminated zone is still open in all directions. The Company's geologists infer that the zone could continue for at least 200 m in a NW-SE direction because of the multiple intersections of the Promontorio mine veins with the Cusi fault along this distance. These intersections provided the fractures and open spaces needed for mineralizing solutions to seep into the host rhyodacite to form the disseminated zone.
The high grades of silver encountered in the development work on Level 9 of the Promontorio mine (Figure 3) reinforces the Company's view that wide zones of potentially-economic silver mineralization occur where the Promontorio main vein (Veta A) is intersected by the "alphabet" veins, such as Veins C, H, K, etc. Vein A (also called the Promontorio vein or main vein) strikes NE and dips steeply NW. Several other veins (the alphabet veins) strike in the same direction, but dip steeply in the opposite direction (SE) such that extensive fracture and stockwork breccia zones occur at the intersections of the veins. This relationship was announced by the Company in 2007 when it obtained historical sampling data from Level 7 of the mine where the H vein intersects Vein A (press release of May 8, 2007). Drill hole DC07B101-B (also shown on Figure 2) was drilled to confirm these data and returned 9.0 m averaging 1,651 g/t Ag (press release of June 19, 2007), which illustrated the veracity of the historical data.
The zone is best illustrated by the samples 2960-2967 that were taken across the strike of the fractured zone. These eight samples cover a sample length of 7.3 meters and average 190.9 g/t Ag, 0.08% Pb, 0.35% Zn and 0.38% Mn, again illustrating the low levels of base metals in this area of the Promontorio mine. The Company's geologists infer that the upper levels of the Promontorio mine are in the very upper portions of the precious metals zone, which indicates that almost the entire zone occurs in the mine area. This has significant positive implications for the exploration and development potential for the Promontorio mine area.
These results from drilling and development work emphasize the importance of the Company's plan to increase exploration and mine development activities at the Promontorio mine. Accelerated underground development will bring forward the timing of increased output from the mine and increase silver production, and in-fill drilling will provide guidance for mine planning towards that goal.
El Gallo: Drilling in this area continues to demonstrate the down-dip continuity of the El Gallo and El Gallo back veins (Figure 4). The data from drilling are also allowing better projection of the orientation of the veins and the Company's geologists are targeting the zone of intersection of these two veins, which is due to their different strikes. The intersection is to the northeast of the view in Figure 4 and is an area that has been the site of historical mining. The mined area, however, is limited to the upper portions of the intersection and the down-dip projection of the intersection is now better understood and will be the target of future drilling. The veins are also open to depth, as shown in Figure 4.
Santa Eduwiges Mine: The multiple intercepts in the Santa Eduwiges area (San Bartolo and San Antonio veins) illustrate the abundance of veinlets that occur in the area. When the veinlets converge or blow out to wider veins, these areas become mineable, as for example the San Bartolo area where the Company is mining at Levels 8 and 10. As additional drill data are obtained, the structures controlling the veins are better understood and this knowledge increases the success of the drilling, as shown by these results in that every hole that was drilled in the Santa Eduwiges area in this recent program has penetrated veinlets with high grades of silver.
Method of Analysis
Samples from the surface drill holes 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.
Samples from underground drill holes were prepared at the Company's lab facility at its Malpaso lab and analyzed by atomic absorption for Cu, Zn, Pb, Bi, Co, Mn, Sb, Cd and Fe. Gold and silver are analyzed by fire assay method. Diamond drill samples sent for analysis consisted of half NQ-size and BQ-size diamond core split on site. The Malpaso laboratory follows the quality control methodology recommended by CANMET of Canada, such as assaying of blanks, duplicate samples, and check assays by commercial laboratories such as Chemex.
The quality assurance-quality control (QA-QC) of Dia Bras has been described in detail in RPA's NI 43-101 report of December 2006 at Cusi.
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 exploration & 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 Bolsa de Valores de Lime and 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.
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.