Denver, CO. - Augusta Resource Corporation (”Augusta”, the Company”) announced that it has fully exercised its option to purchase the Rosemont property in Pima County Arizona. The Company has paid the remaining balance of $CAD 16.1 million, under its purchase option agreement. Augusta now owns a 100% interest in the Rosemont property subject to a 3% NSR.

Gil Clausen, President and Chief Executive Officer said “The 100% ownership of Rosemont gives us added flexibility as we advance through permitting and feasibility work. With the proceeds from the Private Placement announced on March 17, 2006, Augusta expects to be fully funded through to a project financing decision.”

About the Company

Augusta is a mineral exploration and development company responsibly advancing copper and other base metal assets in the U.S. southwest. The Company’s Rosemont Property is located in Pima County, approximately 50 km southeast of Tucson, Arizona, and contains three known potentially open-pit copper/molybdenum (“Cu/Mo”) deposits. The Rosemont deposit contain 6.4 billion lbs of Cu equivalent (442,000,000 tons at 0.73% Cu equivalent) in measured and indicated resources and 1.9 billion lbs of Cu equivalent (145,000,000 tons at 0.67% Cu equivalent) in inferred resources. Augusta has additional exploration properties in Nevada and New Mexico. The Company is traded on the Canadian TSX Venture Exchange under the symbol ARS.

For additional information please visit www.augustaresource.com or contact:

FORWARD LOOKING STATEMENTS

The statements that are not historical facts are forward-looking statements involving known and unknown risks and uncertainties that could cause actual results to vary materially from targeted results. Such risks and uncertainties include those described from time to time in the Corporation's latest annual report and management discussion and analysis. The Corporation assumes no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.