Atna Increases Briggs Gold Resource And Replaces Mined Ounces 

GOLDEN, CO - Atna Resources Ltd. reported the results of the newly completed resource estimate for the Briggs Mine, Inyo County, California. Development drilling during 2011 was successful in expanding the mineral resource base at the Briggs Mine and in replacing the mineral resources mined during 2011. Additionally, drilling completed in 2011 increased the measured and Indicated Resources ("M & I") by nearly 8%. The majority of the increase in the M & I resource is located in the Deep Briggs zone which now contains a resource of over 11.5 million tons grading 0.015 oz/ton gold (10.5 million tonnes grading 0.51 g/t) containing 171,000 ounces.

"Our 2011 drilling campaign added nearly 50,000 ounces to the M & I resource categories and replaced the gold ounces mined at Briggs in 2011. This is a very positive return on our drilling dollars and highlights the potential for additional resource replacement at Briggs in the future. These increases should translate into increased mineral reserves and mine-life for Briggs once design work is completed," said James Hesketh, President and CEO.

A total of 2.6 million tons of ore was mined at Briggs in 2011 at an average grade of 0.016 oz/ton (2.3 million tonnes at 0.55g/t) containing 43,400 ounces. A total of 33,018 ounces of gold were recovered and 32,370 ounces were sold.