Oro Mining Reports Positive Sonic Drill Results and First Quarter Exploration Plan on Its Trinidad Property, Mexico


VANCOUVER, BRITISH COLUMBIA--(Marketwire - Jan. 11, 2011) - Oro Mining Ltd. (TSX VENTURE:OGR) reports positive drill results for the first sonic hole drilled at its 100%-owned Taunus Gold deposit on its Trinidad property Sinaloa, Mexico. Gold composites from the sonic drill hole are higher grade than nearby reverse circulation (RC) holes in both the Eldorado and HS zones. The drill hole also intersected a new gold mineralized zone in-between the Eldorado and HS zones.

The sonic hole drilled to a total depth of 200 metres and intersected five separate gold-bearing intervals as shown in the table below. This is the first hole drilled at Taunus that has intersected both the Eldorado and HS zones. The hole was drilled from an existing ramp inside the recently dewatered pit.

Sonic Hole From (m)  To (m) Interval (m) Gold Grade(g/t) Zone
10TRSN001 25.8 36.5 10.7 5.0 Eldorado zone (upper zone)
  45.4 53.8 8.4 1.3 Eldorado zone (lower Zone)
  79.3 85.0 5.7 1.5 below Eldorado zone (Shadow zone)
  138.4 167.4 29.0 4.6 HS zone
  including 149.4 162.5 13.1 9.5 HS zone
  181.9 185.4 3.5 0.5 below HS zone
  189.7 193.4 3.7 2.6 below HS zone

Eldorado zone

In the Eldorado zone, gold grades from the sonic drilling are significantly higher than nearby RC and diamond drill holes. Sonic drill hole 1 intersected two intervals: 5.0 g/t gold over 10.7m at and 1.3 g/t over 8.4m. The composite(1) from the beginning of the first interval to the end of the second interval is 2.3 g/t gold over 28 metres, as compared to 0.7 g/t gold over 34 metres and 1.6 g/t gold over 34 metres in the adjacent(2) RC and diamond holes respectively (Figures 1 to 3).

"These sonic drill results are significant being 150 to 300 per cent higher in gold grade than adjacent diamond and RC holes. Based on these results, we are planning a comprehensive sonic drilling campaign which has the potential to significantly increase the gold grade in the Eldorado zone," commented Frank Powell, Executive VP of Oro Mining.

To view figures 1 to 3 click on the following link: http://media3.marketwire.com/docs/OROfig1to3.pdf

Oro Mining recently released a resource estimate on the Taunus deposit as shown in the table below. The grades in the Eldorado zone were significantly lower than the overall grade of the deposit where over 95 per cent of the drill holes were RC holes. The average grade of the Eldorado zone in the indicated category is 0.95 g/t gold representing approximately 40% of the reported indicated resource, while the average grade of the Eldorado zone in the inferred category is 0.88 g/t gold representing approximately 1% of the reported inferred resource.

Taunus Resources at a 0.3 g/t gold cut-off    
     
Eldorado zone K-Tonnes Gold Grade Gold k-Oz % of Total Resource
Indicated Resource 2,363 0.95 72 39%
Inferred Resource 53 0.88 2 1%
         
Total Taunus Indicated Resource 3,868 1.51 187 100%
Total Taunus Inferred Resource 2,539 1.45 118 100%
1) Mineral resources are not mineral reserves and have not demonstrated economic viability. There is no certainty that all or any part of the Mineral Resources will be converted into Mineral Reserves.
2) Mineral Resource tonnage and contained metal have been rounded to reflect the accuracy of the estimate.
3) Resources for Taunus are stated as contained within a potentially, economically minable pit using a 0.3 g/t gold cutoff grade.
4) Pit optimization for Taunus is based on an assumed gold price of $1,200/ounce; metallurgical recovery of 90%; and processing cost of $12.00/tonne. Resources stated above a 2.0 Au equivalent contained within potentially minable vein wireframes using gold:silver ratio of 63:1. Metallurgical recoveries assumed at 100%.

HS zone

In the HS zone, located approximately 45 to 80 metres below the Eldorado Zone, the sonic hole intersected 4.6 g/t gold over 29 metres, including 9.5 g/t gold over 13.1 metres, as compared to 1.45 g/t gold over 31.8 metres in the nearby RC hole(3). The nearest diamond drill hole, 09TR019, is located approximately 10 to 30 metres away and intersected 30 metres of 6.3 g/t gold. Another diamond drill hole located 30 metres away intersected 5.2 g/t gold over 18.7 metres. Results of the sonic hole in the HS zone are significantly higher than the RC hole, and similar in grade to the nearest diamond holes (Figures 4 and 5).

To view figures 4 and 5 click on the following link: http://media3.marketwire.com/docs/OROfig4and5.pdf

The recent resource estimate in the HS zone, reports an average grade of 4.33 g/t gold in the indicated category and 2.75 g/t in the inferred category. This estimate used only diamond holes; RC holes were not used in the estimation of the HS zone. The upcoming sonic drill program will focus on areas in the HS zone that are currently in the inferred category, which could potentially increase the gold grade of this zone.

Taunus Resources at 0.3 g/t gold cut-off  
HS zone K-Tonnes Gold Grade Gold K-Oz % of Total Resource
Indicated Resource 611 4.33 85 45%
Inferred Resource 756 2.75 67 56%
1) Mineral resources are not mineral reserves and have not demonstrated economic viability. There is no certainty that all or any part of the Mineral Resources will be converted into Mineral Reserves.
2) Mineral Resource tonnage and contained metal have been rounded to reflect the accuracy of the estimate.
3) Resources for Taunus are stated as contained within a potentially, economically minable pit using a 0.3 g/t gold cutoff grade.
4) Pit optimization for Taunus is based on an assumed gold price of $1,200/ounce; metallurgical recovery of 90%; and processing cost of $12.00/tonne. Resources stated above a 2.0 Au equivalent contained within potentially minable vein wireframes using gold:silver ratio of 63:1. Metallurgical recoveries assumed at 100%.

Additional zones

The sonic hole intersected a new zone below the Eldorado zone of 5.7 metres at 1.45 g/t gold from 79.3 to 85.0 metres. This intersection is located in the "shadow zone", which is the area that has not been accessible by drilling due to the location of the pit. These results indicate resource potential in this area which will be investigated with the sonic drilling (Figures 6 and 7).

To view figures 6 and 7 click on the following link: http://media3.marketwire.com/docs/OROfig6and7.pdf

Exploration Plan

Oro Mining plans to drill approximately 5,000 metres of sonic and diamond drilling in the first quarter of 2010. A significant portion of this drilling will be by sonic within the recently dewatered pit with the following objectives to increase the Taunus resource base by: 1) increasing the gold grade of the Eldorado zone; 2) assess the untested zone in-between the Eldorado and HS zones; 3) target potential high-grade gold feeders; 4) target offset and extension zones; and 5) potentially increase the gold grade of the HS zones in the inferred resource category. In addition, the Company plans to continue drilling with a diamond drill rig targeting potential satellite zones in close proximity to the Taunus gold deposit.

Sonic drilling is a relatively new alternative for drilling rock. The drill uses sonic vibrations applied to the pipe to drill and retrieve continuous samples from broken and semi-consolidated material without the use of water or mud. Many types of conventional drilling techniques which rely on fluid or air circulation do not efficiently recover soft, unstable, varied and highly broken material. Additional information on this drilling technique can be sourced on Oro Mining's web site.

Oro Mining has also drilled 11 sonic holes on the historic leach pad and will be releasing the results shortly.

About Oro Mining

Oro Mining is a publicly-listed company on the TSX Venture Exchange with properties situated in prolific mining camps in Sinaloa and Zacatecas, Mexico. Oro Mining's focus is to advance its projects towards production while continuing to make exploration discoveries on its extensive land holdings. The district-scale Trinidad property that hosts the Taunus gold deposit continues to be the Oro Mining's priority project. Our mission is to create exceptional value for shareholders through, exploration discovery, resource growth, mine development and production while providing sustainable benefits to our staff, the environment, and the communities where we operate.

Quality Assurance - Quality Control

The Trinidad project exploration is under the direction of Frank Powell, Executive Vice President Oro Gold Resources Ltd. Gary Lustig, P.Geo, a qualified person as designated by National Instrument 43-101 has reviewed the technical content of this release. Thorough quality assurance and quality control program (QA/QC) protocol was utilized on the project including duplicate, blank and standard samples with each batch of assays. The sonic core samples were submitted directly to Inspectorate de Mexico, S.A de C.V. for preparation in Durango, Mexico, with analysis in Reno, Nevada. Analysis was conducted on 1 assay ton samples with over 20% as QA/QC samples. Analysis of gold was by fire assay, with a gravimetric finish on samples exceeding 5 g/t gold. Silver analysis was by ICP-AES following aqua regia digestion (geochem). The Taunus and El Compas mineral resource estimations were completed by SRK Consulting Ltd ("SRK"). The person responsible for the resource estimates on behalf of SRK Consulting Ltd. is Jeffry Volk, MSc, CPG, FAusIMM, a Qualified Person as defined by National Instrument 43-101, and has reviewed the content of this press release.

ON BEHALF OF THE BOARD OF DIRECTORS

John Brownlie, CEO & COO

Some statements in this release may contain forward-looking information. These statements include, but are not limited to, statements with respect to future exploration, development and production activities and future expenditures. These statements address future events and conditions and, as such, involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the statements.


(1) The composite includes an internal barren interval of 8.9m at 0.06 g/t gold and is calculated for comparison purposes only.

(2) The two holes are not considered to be twins since the sonic hole was drilled vertically and the other holes were angle holes. The distance between the sonic hole and the RC hole is 3 to 7 metres, and the distance between the sonic hole and diamond hole is 8 to 20 metres.

(3) The two holes are not considered to be twins since the sonic hole was drilled at 85 degrees to the south and the RC hole was drilled at -60 degrees to the southwest. The distance between the holes ranges from approximately 4 to 6 metres.

Contact Information: Oro Mining Ltd.
John Brownlie
CEO & COO
604 646-1580
604 642-2411 (FAX)
www.orogoldresources.com