2011 News Releases
Hydrology Tests Confirms Suitable Conditions for In-Situ Recovery at Excelsior's Gunnison Project
September 6, 2011
Excelsior Mining Corp. (TSX-V: MIN) (Frankfurt: 3XS) (OTCQX: EXMGF) ("Excelsior") is pleased to announce reuslts from two comprehensive hydrological tests conducted at the North Star Deposit. The results generated hydrological conductivities in the range expected for a fractured deposit and show the deposit is suitable for in-situ recovery (ISR). The North Star Deposit is part of the Gunnison Copper Property located within the copper porphyry belt in southern Arizona.
"We are very pleased with the results from this initial hydrological testing. We have successfully achieved another milestone in demonstrating suitable hydrological conditions for ISR at the North Star Deposit," says Stephen Twyerould, President and CEO of Excelsior. "These relults will be combined with new metallurgical data to complete a Preliminary Economic Assessment expected later this year. Further hydrological and metallurgical testing will be carried out as we continue driving our Project towards production."
The North Star Deposit currently contains an indicated oxide copper resource of 3.21 billion pounds (511 million tons at 0.31% copper) and an additional inferred oxide copper resource of 0.88 billion pounds (159 million tons at 0.28% copper). For further details on the resource estimate, please see the news release dated July 19, 2011.
Two hydrological tests were completed on holes NSH-01 and NSH-02 and included pumping and injecting water to measure groundwater parameters, extensive down hole geophysical logging, geological logging and assaying, and advanced electrical geophysics. The two new tests complement previous testing in the lat 1990's by Magma Copper Corporation (BHP-Billiton). The holes are all located in the central portion of the North Star Deposit as shown in the figure at: http://excelsiormining.com/Projects/GunnisonProject/Hydrology_Map.pdf
Hydrological conductivities ("K values") are a measure of the efficiency with which water moves through the rock and are measured as feet per day (ft/d). NSH-01 had a K value of 0.08 ft/d measued over an interval of 394 feet (from 702 feet to 1,096 feet), representing the screened interval of the hold. NSH-02 had a K value of 5.9 ft/d measured over an interval of 656 feet (from 608 feet to 1,264 feet). The average K value for the two holes is approximately 2.9 ft/d. The K values achieved are entirely consistent with K values from similar ISR projects.
Excelsior's hydrological testing was supervised by Michael W. Bostic, R.G., Principal Hydrogeologist from BasinWells Associates, PLLC and a Qualified Person as defined by NI 43-101. Mer. Bostic has reviewed and is responsible for the technical information contained in this news release with respect to Stephen Twyerould, Fellow of AUSIMM, President and CEO of Excelsior and a Qualified Person as defined by NI 43-101. Mer. Twyerould has reviewed and verified the data disclosed in this news release with respect to the resource estimate.
Excelsior is an exploration and development company with a copper project located within the copper porphyry belt of Arizona. The Gunnison Copper Project is located close to the required infrastructure and with its in-situ recovery potential, is intended for near-term production. The Excelsior team consists of experienced professionals with proven track records of advancing projects towards production.
Further details about Excelsior can be found at: http://www.excelsiormining.com. Further information about the Gunnison Copper Project can be found in the technical report filed on SEDAR at www.sedar.com entitled: Gunnison Copper Project, Cochise County, Arizona, USA, Mineral Resource of the North Star dated August 31, 2011.
ON BEHALF OF THE EXCELSIOR BOARD
Cautionary Note Regarding Forward-Looking Information
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