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US Tungsten Completes Guide 7 Geological Report on Montana Calvert Tungsten Property

US Tungsten Corporation ("US Tungsten" or "USTU"), a company focused on becoming a near-term North American tungsten producer with the re-development of the historically productive Calvert Mine in SW Montana, is pleased to announce the completion of their Guide 7 Geological Report on the Calvert Tungsten Property, Beaverhead County, Montana.

Report Summary:

The Calvert Mine Tungsten property is located in southwestern Montana approximately 40 miles southwest of the City of Butte and 11 miles northwest of the village of Wise River. The Calvert Mine property is located within section 12, Township 1 North, Range 13 West and centered on 113.158W Longitude and 45.854N Latitude. The aggregate area covered by the claims is 1,404.88 acres.

The Calvert Mine property consists of 68 Lode claims (totaling 1,404.88 acres) located entirely on state land within the Beaverhead County Recording District.

The Calvert area is part of the north western portion of the eastern Pioneer Mountains and is underlain by early Proterozoic crystalline rocks of the belt supergroup associated with roof pendants, thrust blocks of Mississippian to Cretaceous aged sediments and metavolcanics. The entire package has been intruded by Tertiary and late Cretaceous tonalites, granites and andesite dykes. The area lies on the northern edge of the Pioneer batholith, a composite granitic body of late Cretaceous to early Paleocene age that intruded the previously folded and faulted sediments.

The main units of interest from a tungsten exploration point of view are the late Cretaceous intrusions in contact with the Mississippian to lower Pennsylvanian calcareous sediments and limestone. These units form a narrow northwest trending belt that parallel the regional structures and make an excellent target for additional exploration.

Exploration activities on the Calvert Mine site are strictly historical in nature. Tungsten mineralization on the Calvert property was first discovered in 1956 during a time when the US government provided aid for exploration through the Defense Minerals Exploration Administration. In the same year Minerals Engineering Company of Grand Junction, Colorado leased the property and completed an exploration drill program in the same year leading to a production decision in September 1956. Mining operations by open pit methods were completed between the periods 1956-1957 and 1959-1962 where 217,937 tons of ore were produced at a grade of 1.10% WO3 and shipped to the company processing facilities at Glen Montana. Additional exploration campaigns were completed in 1966, 1967 and 1971 by Minerals Exploration Company resulting in a historical proven in-ground reserve of 128,000 tons at a grade of 1.1% WO3. No recent exploration campaigns have been completed on the Calvert Mine Tungsten property.

An exploration program is recommended including drilling to confirm the existence of these historical reserves below the Calvert open pit and its potential down plunge extension to the southeast.

A copy of the Geological Report will be available on the company website at

Michael Olsher Ph.D., CEO -- US Tungsten -- commented:

"As the company's CEO, I am very excited by the findings in this report and we feel strongly that the Calvert Mine has the potential to become the United States' first producing tungsten mine in several decades." Dr. Olsher further states "This report covers only two of the 68 claims we have in the Calvert Area. We look forward to further exploration of our existing claims".


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