The Three Brothers Zone is a molybdenum and copper mine located in King county, Washington at an elevation of 4,600 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: 4,600 Feet (1,402 Meters)
Commodity: Molybdenum, Copper
Lat, Long: 47.5181, -121.34440
Map: View on Google Maps
Satelite View
MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.
Three Brothers Zone MRDS details
Site Name
Primary: Three Brothers Zone
Commodity
Primary: Molybdenum
Primary: Copper
Tertiary: Lead
Tertiary: Arsenic
Tertiary: Gold
Tertiary: Silver
Location
State: Washington
County: King
District: Snoqualmie 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: In Snoqualmie National Forest Near Alpine Lakes Wilderness
Holdings
Not available
Workings
Not available
Ownership
Owner Name: United Cascade Mining Co., Inc.
Years: 1990 -
Production
Not available
Deposit
Record Type: Site
Operation Category: Occurrence
Deposit Type: porphyry Cu
Operation Type: Unknown
Years of Production:
Organization:
Significant: N
Deposit Size: S
Physiography
General Physiographic Area: Pacific Mountain System
Physiographic Province: Cascade-Sierra Mountains
Physiographic Section: Northern Cascade Mountains
Mineral Deposit Model
Model Name: Porphyry Cu
Orebody
Form: DISSEMINATED, STOCKWORK
Structure
Type: R
Description: Part Of Ne-Trending En-Echelon Belt Of Nw-Striking Faults, Fractures, And Breccia Pipes
Type: L
Description: Brecciation Of Host Rocks
Alterations
Alteration Type: L
Alteration Text: Potassic, Propylitic, Silicification
Rocks
Not available
Analytical Data
Analytical Data: SEE DERKEY AND OTHERS (1990) FOR ANALYTICAL DATA FOR CLIPPER
Materials
Ore: Pyrrhotite
Ore: Chalcopyrite
Ore: Galena
Ore: Molybdenite
Ore: Pyrite
Ore: Magnetite
Ore: Hematite
Gangue: Quartz
Gangue: Siderite
Gangue: Chlorite
Comments
Comment (Workings): ADIT
Comment (Geology): GEOLOGY PRESUMED SAME AS AT CLIPPER
Comment (Deposit): CONSIDERED PART OF CLIPPER BY DERKEY AND OTHERS (1990)
Comment (Deposit): DEPOSIT LIES BETWEEN TWO STEEPLY DIPPING FAULTS
Comment (General): Look at data in the Middle Fork Property file for more information. The Three Brothers is near the northern end of a string of mineralized, fractured zones, probably between the Hawk and Red Face zones.
References
Reference (Deposit): U.S. GEOLOGICAL SURVEY BULLETIN 1542-E, 1989, FIG. 11, P. 98; P. 101-102.
Reference (Deposit): GUALTIERI, J.L., THURBER, H.K., MILLER, M.S., MCMAHAN, A.B., AND FEDERSPIEL, F.F., 1975, MINERAL RESOURCES OF ADDITIONS TO THE ALPINE LAKES STUDY AREA, CHELAN, KING, AND KITTITAS COUNTIES, WASHINGTON: U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 75-3, P. 51-61.
Reference (Deposit): DERKEY, R.E., JOSEPH, N.L., AND LASMANIS, RAYMOND, 1990, METAL MINES OF WASHINGTON - PRELIMINARY REPORT: WASHINGTON DIVISION OF GEOLOGY AND EARTH RESOURCES OPEN-FILE REPORT 90-18, P. 109-110.
Reference (Deposit): GUALTIERI, J.L., SIMMONS, G.C., THURBER, H.K., AND MILLER, M.S., 1973, MINERAL RESOURCES OF THE ALPINE LAKES STUDY AREA, CHELAN, KING, AND KITTITAS COUNTIES, WASHINGTON: U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 1918, P. 71-74.
Reference (Deposit): HOLLISTER, V.F., 1979, PROPHYRY COPPER-TYPE DEPOSITS OF THE CASCADE VOLCANIC ARC, WASHINGTON: MINERALS SCIENCE AND ENGINEERING, V. 11, P. 32.
Washington Gold
"Where to Find Gold in Washington" 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 Arizona. Read more: Where to Find Gold in Washington.
