The Cumo Prospect is a copper and molybdenum mine located in Boise county, Idaho at an elevation of 5,499 feet.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Elevation: 5,499 Feet (1,676 Meters)
Commodity: Copper, Molybdenum
Lat, Long: 44.0361, -115.78330
Map: View on Google Maps
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Cumo Prospect MRDS details
Site Name
Primary: Cumo Prospect
Secondary: Cumo Moly Deposit
Commodity
Primary: Copper
Primary: Molybdenum
Secondary: Silver
Secondary: Tungsten
Tertiary: Lead
Tertiary: Gallium
Tertiary: Zinc
Tertiary: Rhenium
Location
State: Idaho
County: Boise
District: Grimes Pass District
Land Status
Land ownership: National Forest
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.
Administrative Organization: Boise National Forest
Holdings
Not available
Workings
Not available
Ownership
Owner Name: Amax Exploration, Inc.
Years: 1974 -
Owner Name: Mosquito Consolidated Gold Mines Ltd
Percent: 100.0
Home Office: Vancouver BC
Info Year: 2010
Production
Not available
Deposit
Record Type: Deposit
Operation Category: Prospect
Deposit Type: Cu-Mo porphyry
Operation Type: Unknown
Discovery Method: Unknown
Years of Production:
Organization:
Significant: Y
Deposit Size: S
Physiography
General Physiographic Area: Rocky Mountain System
Physiographic Province: Northern Rocky Mountains
Physiographic Detail: Sawtooth Mountains
Mineral Deposit Model
Model Name: Porphyry Cu-Mo
Model Name: Porphyry Mo, low-F
Orebody
Form: tabular
Structure
Type: L
Structure: stockwork
Description: Fractures, Shears And Faults, Breccia
Alterations
Alteration Type: L
Alteration: Propylitization
Alteration Type: L
Alteration: Silicification
Alteration Text: Silicification, Argillization, Propylitization, Potassic, Oxidation
Alteration Type: L
Alteration: Argillization
Alteration Type: L
Alteration: Potassic
Alteration Type: L
Alteration: Oxidation
Rocks
Name: Dacite
Role: Associated
Age Type: Associated Rock
Age Young: Early Permian
Name: Dacite
Role: Associated
Age Type: Host Rock
Age Young: Early Permian
Analytical Data
Analytical Data: 4 DACITE PORPHYRY SAMPLES GAVE 6 - 35 PPM MO, 54 - 360 PPM CU
Analytical Data: 2 ANDESITE SAMPLES GAVE 2 - 3 PPM MO, 1200 - 1500 PPM CU
Analytical Data: 1 LAMPROPHYRE SAMPLE HAD 1 PPM MO, 420 PPM CU
Materials
Ore: Galena
Ore: Sphalerite
Ore: Chalcocite
Ore: Covellite
Ore: Chalcopyrite
Ore: Molybdenite
Gangue: Chlorite
Gangue: Quartz
Gangue: Pyrite
Gangue: Biotite
Gangue: Plagioclase
Gangue: Epidote
Gangue: Calcite
Comments
Comment (Reserve-Resource): The Cumo deposit is estimated to contain 1,258,000,000 tons of mineralized material having an average grade of 0.059 percent MoS2, and 0.074 percent copper (Rostad, 1978). The deposit is not mineable under present economic conditions, however, it should be considered as a potential future resource of molybdenum.
Comment (Geology): The deposit is located and controlled by the strong, northeast-trending trans-Challis fault system, and, to a lesser extent, by the more or less parallel porphyritic rhyolite dikes that make up the associated porphyry belt.
Comment (Development): CUMO PROSPECT FIRST MENTIONED 1970
Comment (Deposit): MOST VEINS ONLY 2 MM WIDE
Comment (Workings): The altered granodiorite and the steep-dipping rhyolite dikes of the deposit presented drilling problems to the exploration program as the drill bit tended to deflect away from the hard, brittle rhyolite into the softer altered granodiorite. There has been no known exploration or development of the deposit since 1984.
Comment (Location): The Cumo prospect is 14 mi north of Idaho City, Idaho. The prospect is accessible by unimproved road up Grimes Creek northeast from Pioneerville. It is on the Grimes Pass topographic map, and in the Boise National Forest. The prospect is located on a steep, north-facing, forested slope between altitudes 5500 and 6500 ft, and chiefly between Copper and Cricket Creeks, both of which flow north into Grimes Creek.
Comment (Analytical Data): Description from Thor Kiilsgaard unpublished description. Re-assay of pulps from drill core for minor and trace elements indicates average elemental concentrations of 2.8 ppm Ag, 17.9 ppm Ga. In the Mo zone the average concentration of Re is 43 ppm (Mosquito Consolidated Gold Mines, Ltd., 2007).
Comment (Ownership): The deposit was discovered by AMAX Exploration in 1963, and from 1968 to 1984 was continuously explored, including efforts by Curwood Mining Co., Midwest Oil Co., and AMAX/AMOCO (Baker, 1985). AMAX and partners drilled a geochemical anomaly - 1968-1982, Mosquito Resources had the property sometime later and apparently sold it to Kobex Resources around 2006 and then resumed control in Oct. 2006.
References
Reference (Deposit): 1971 GEOLMAP MIDWEST OIL CO., WHITNEY M. S. THESIS
Reference (Reserve-Resource): MOSQUITO CONSOLIDATED GOLD MINES LIMITED, 2009, MOSQUITO FILES CUMO NI 43-101, ANNOUNCES 1.3 BILLION TONS INDICATED, 2.2 BILLION TONS INFERRED OF HIGHER-GRADE MULTI-ELEMENT MINERALIZATION: NI43-101 report filed by Mosquite Consolidated Gold Mines Limited with SEDAR [www.mosquitogold.com] accessed from http://www.infomine.com/index/pr/PA751752.PDF, July 14, 2009.
URL: http://www.infomine.com/index/pr/PA751752.PDF
Reference (Deposit): Worthington, J.e., 2007, Porphyry and other molybdenum deposits of Idaho and Montana: Idaho Geological Survey Technical Report 07-3, University of Idaho, Moscow, Idaho
Reference (Reserve-Resource): George Cross Newsletter, 1995, Report on CUMO drilling, February 16.
Reference (Deposit): SHANNON, S.S., JR., 1971, EVALUATION OF COPPER AND MOLYBDENUM GEOCHEMICAL ANOMALIES AT THE CUMO PROSPECT, BOISE COUNTY, IDAHO, IN BOYLE, R.W., AND MCGERRIGLE, J.I., EDS., GEOCHEMICAL EXPLORATION: CANADIAN INST. OF MINING AND METALL. SPEC. VOL. II, P. 247-250.
Reference (General): Holmgren, J. A., 2008 , SUMMARY REPORT ON THE CUMO PROPERTY BOISE COUNTY, IDAHO, for Mosquito Consolidated Gold Mines: CUMO 2008 Technical Report
Reference (Geology): Killsgaard, T.H, Fisher, F.S. and Bennet, E.H., 1989, Gold-Silver Deposits Associated with the Trans-Challis Fault System, Idaho; USGS Bull 1857-B, p. B22-B44
Reference (Geology): Kiilsgaard, T.H., and Bennett, E.H., 1995, Tertiary molybdenum stockworks, in Geology and Mineral Resource Assessments of the Challis 1o x 2o Quadrangle, Idaho: U.S. Geological Survey Professional Paper 1525, p. 131-134.
Reference (Reserve-Resource): Rostad, Ora, 1978, Discussion notes: Economic Geology, vol. 73, p. 1366-1367.
Reference (Geology): Baker, Donald J., 1985, Geology of the Cumo molybdenum-copper system, Boise County, Idaho: Geological Society of America Abstracts with Programs, 1985, V. 17, No. 4, p. 207.
Reference (Analytical Data): Mosquito Consolidated Gold Mines, Ltd., 2007, Mosquito confirms historical assays at Cumo: on line at http://www.mosquitogold.com, 6/11/07.
URL: http://www.mosquitogold.com
Reference (Geology): Baker, D.J., 1983, The CUMO Molybdenite System, Boise, Idaho, A Comprehensive Summary?,Climax Molybdenum Company, April 1983, unpublished.
Reference (Deposit): 1975 COMPILE IDAHO DEPT LABOR AND INDUSTRIAL SERVICES, ADDENDUM
Reference (Deposit): 1974 GEOLMAP AMAX EXPLORATION, INC., WHITNEY M. S. THESIS
Reference (Geology): Kiilsgaard, T.H., and Lewis, R.S., 1985, Plutonic rocks of Cretaceous age and faults in the Atlanta lobe of the Idaho batholith, Challis quadrangle: U.S. Geological Survey Bulletin 1658, Chapter B.
Reference (Deposit): WHITNEY, M. S., 1975 , GEOLOGY OF THE CUMO PROSPECT, BOISE COUNTY, IDAHO: GOLDEN, COLORADO, COLORADO SCHOOL OF MINES, M. S. THESIS, 84 P.
Reference (Deposit): IDAHO DEPT. OF LABOR AND INDUSTRIAL SERVICES, 1975 , FIRST ANNUAL REPORT ADDENDUM, JULY 1 , 1974 - JUNE 30 , 1975 , 95 P.
Reference (Geology): Anderson, A.L., 1947, Geology and ore deposits of the Boise Basin, Idaho: U.S. Geological Survey Bulletin 944-C.
Reference (Reserve-Resource): Jones, Ivor, et al, 2011, Resource Estimate Update May 2011, NI 43-101 Technical Report prepared for Mosquito Consolidated Gold Mines Ltd. Cumo Project; submitted to sedar.com on June 15, 2011, 223 pages
Pages: 125-126
URL: http://sedar.com
Idaho Gold
"Where to Find Gold in Idaho" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in Idaho. Read more: Where to Find Gold in Idaho.
