Augusta Reports Significant Increase in Rosemont Copper/Moly Resource

VANCOUVER, Jan. 24 /PRNewswire-FirstCall/ -- Augusta Resource Corporation ("Augusta" or the "Company") today announced its 2006 Rosemont Deposit Mineral Resource Statement. Since acquiring the Rosemont property in June 2005, the Company has been on a fast-track program to complete drilling and produce a Canadian National Instrument 43-101 compliant resource estimate. The Company is currently conducting a pre-feasibility study in order to advance the development of the Rosemont copper project towards open-pit production.

Significant improvements are reflected in the Statement (excluding satellite deposits) when compared with the historic resource reported by Anamax (Pincock, Allen and Holt - 1977). The completion of the 2005 exploration program enabled the remodeling of the deposit and a new estimation of mineral resources. The following results reflect a potential single open pit, exclusive of the other satellite deposits on the property:

- A 23% increase in copper pounds in the measured and indicated category (greater than (equal sign) 0.2% Cu) to bring the total copper in the measured and indicated category to 4.54 billion pounds; - An additional 1.3 billion pounds of copper in the inferred resources category (greater than (equal sign) 0.2% Cu); - A 16% increase in molybdenum ("moly") pounds in measured and indicated, bringing the total to 132 million pounds; - An additional 43 million pounds of moly in the inferred resources category; - Tonnage increased by 125 million tons in the measured and indicated category to a total of 442 million tons. Approximately 145 million tons were added in the inferred category; - The copper equivalent grade(x) in measured and indicated now stands at 0.73%CuEq (greater than (equal sign) 0.2% total Cu) and 0.81% CuEq (greater than (equal sign) 0.3% total Cu). (x) Copper equivalent based on three-year trailing average prices of $1.25/lb Cu and $18/lb Mo. Table 1: Measured Resources ------------------------------------------------------------------------- lbs Cu Tons %Cu lbs Cu lbs Mo Eq.(x) Cutoff (thousands) %Cu %Mo Eq.(x) (millions) (millions) (millions) ------------------------------------------------------------------------- 0.20% Cu 94,000 0.55 0.015 0.77 1,040 28 1,440 0.25% Cu 87,000 0.58 0.015 0.79 1,000 26 1,380 0.30% Cu 80,000 0.60 0.015 0.82 970 24 1,310 ------------------------------------------------------------------------- Table 2: Indicated Resources ------------------------------------------------------------------------- lbs Cu Tons %Cu lbs Cu lbs Mo Eq.(x) Cutoff (thousands) %Cu %Mo Eq.(x) (millions) (millions) (millions) ------------------------------------------------------------------------- 0.20% Cu 348,000 0.50 0.015 0.72 3,500 104 5,010 0.25% Cu 311,000 0.54 0.016 0.77 3,350 100 4,800 0.30% Cu 277,000 0.57 0.016 0.80 3,160 90 4,450 ------------------------------------------------------------------------- Table 3: Total Combined Measured and Indicated Resources ------------------------------------------------------------------------- lbs Cu Tons %Cu lbs Cu lbs Mo Eq.(x) Cutoff (thousands) %Cu %Mo Eq.(x) (millions) (millions) (millions) ------------------------------------------------------------------------- 0.20% Cu 442,000 0.51 0.015 0.73 4,540 132 6,450 0.25% Cu 398,000 0.55 0.016 0.78 4,350 126 6,180 0.30% Cu 357,000 0.58 0.016 0.81 4,130 114 5,760 ------------------------------------------------------------------------- Table 4: Inferred Resources ------------------------------------------------------------------------- lbs Cu Tons %Cu lbs Cu lbs Mo Eq.(x) Cutoff (thousands) %Cu %Mo Eq.(x) (millions) (millions) (millions) ------------------------------------------------------------------------- 0.20% Cu 145,000 0.45 0.015 0.67 1,300 43 1,930 0.25% Cu 116,000 0.51 0.016 0.74 1,170 37 1,710 0.30% Cu 96,000 0.56 0.017 0.80 1,070 33 1,540 ------------------------------------------------------------------------- (x) Copper equivalent based on three-year trailing average prices of $1.25/lb Cu and $18/lb Mo. Tons refer to short tons (2000 lbs).

"It is very gratifying to see results from our drilling program confirming Rosemont as one of the best undeveloped open pit copper projects in the world and the only significant undeveloped one in the U.S." said Gil Clausen, President of Augusta.

Mike Clarke, VP Exploration for Augusta, added, "The drilling we carried out in building this resource has added greatly to our understanding of the geology of the deposit. This experience will be applied to the exploration for extensions of the Rosemont deposit and satellite deposits. Our attention will focus first on an area of prime exploration potential that extends 1.4 km north of the Rosemont deposit to the Broadtop Butte prospect, where old Anamax drilling defined another significant historical copper/molybdenum resource on our property."

A reported average silver grade of 7.2 g/ton was reported in the 2005 drill hole program. However, silver was assayed only sporadically in the historic work; therefore, there is insufficient data to categorize a silver resource at this time. The Company is excited about the silver potential of the deposit and further assay work is planned to establish a resource.

A new NI 43-101 report on the Rosemont Property will be available within 45 days on SEDAR at http://www.sedar.com/.

Qualified Person ----------------

Augusta Resource Corporation has retained WLR Consulting, Inc. (WLRC) of Lakewood, Colorado to estimate the Rosemont Project mineral resources as a part of a pre-feasibility mining study that is presently in progress. The mineral resource estimation work was performed by or under the direction of Mr. William L. Rose, P.E., WLRC's Principal Mining Engineer and an independent Qualified Person under the standards set forth by Canadian National Instrument 43-101.

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. 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 http://www.augustaresource.com/ or contact:

Gil Clausen, President and CEO Phone: [phone] Fax: [phone] Roth, Roth Investor Relations Phone: [phone] Fax: [phone] BEHALF OF THE BOARD OF DIRECTORS "Gil Clausen" -------------------- Gil Clausen President and CEO 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.

The TSX Venture Exchange does not accept responsibility for the

adequacy or accuracy of this release.