Atna Drills 305 Feet Grading 0.074 oz/ton Gold at Columbia Gold Project

 

GOLDEN, CO - Atna Resources Ltd. reported positive results in the 2012 metallurgical drill program at its Columbia Gold Project, Lewis & Clark County, Montana. Atna completed seven reverse circulation rotary holes to obtain metallurgical samples for additional process optimization studies. Total footage drilled was 3,468 feet (1,057 m). Holes in this program were drilled down the structural zones to obtain large quantities of mineralized sample material and the intercept lengths do not represent true thicknesses. The long, down-structure intercepts provide strong support for the down-dip continuity of the gold and silver grades in both the Columbia and Donnely vein systems and provides additional support for the resource estimate detailed in the 2010 NI43-101 Technical Report.

Highlights of the drill results include: 190 feet (57.9 m) grading 0.067 oz/ton gold (2.3 g/t) and 0.42 oz/ton silver (14.5 g/t) in hole number COL12-001; 305 feet (93.0 m) grading 0.074 oz/ton gold (2.5 g/t) and 0.62 oz/ton silver (21.2 g/t) in hole number COL12-00; 170 feet (51.8 m) grading 0.084 oz/ton gold (2.9 g/t) and 0.34 oz/ton silver (11.7 g/t) in hole number COL12-003; 455 feet (138.7 m) grading 0.033 oz/ton gold (1.1 g/t) and 0.10 oz/ton silver (3.5 g/t) in hole number COL12-005.

James Hesketh, President & CEO said, "The results from the metallurgical drilling program at Columbia are encouraging and accomplished three key goals necessary to move the project towards permitting and production: The holes confirmed strong continuity down the vein and stockwork zones in both the Columbia and Donnely vein systems; They provided ample materials for completion of the metallurgical testing necessary for feasibility level engineering; and Several of the holes will advance the environmental assessment of the mine site with the installation of groundwater monitoring piezometers."

The Columbia project has an M&I Resource of 741,700 ozs of gold (16.7 million tons grading 0.045 oz/ton) and an inferred resource of 453,600 ozs of gold (10.7 million tons grading 0.042 oz/ton).

In addition to drilling, environmental baseline data gathering continued at Columbia. Monitoring of water resources has been conducted at the Project since the 1990s and has yielded an extensive water quality database. The program was expanded in 2012 with the addition of eight groundwater piezometers and a geomorphic survey of stream reaches. The collected groundwater information will support evaluation of mine water issues such as water supply and dewatering needs. The geomorphic survey is the initial step in characterizing aquatic habitat in the area. The environmental program was also expanded to include terrestrial resources including wildlife, vegetation and wetlands. Monitoring included surveys for threatened, endangered, or sensitive species. These investigations will continue through the 2013 field season.

Additional metallurgical test work will be conducted utilizing samples from this drilling program to further support the currently selected flotation and gravity gold recovery process. Atna's goal is to continue to develop base data to support the completion over the next year of a Mine Plan of Operations as a basis to commence the permitting process at Columbia.

Gold mineralization at Columbia is considered a Tertiary-age, low-sulfidation, epithermal volcanic-hosted quartz-adularia vein system. Mineralization is associated two high-angle fault zones which host the two principal vein and stockwork vein zones at the property know as the Columbia and Donnely veins. The veins are exposed on the surface for over 7,000 feet (2,100 m) in a north-south direction and have been explored to a depth of over 500 feet (150 m) vertically. Gold and silver mineralization is accompanied by broad zones of argillic to propylitic alteration of the dominantly mafic volcanic flows which host the deposit.