Iron Mountain Mine (Number 8; Confidence; Old Mine), Iron Mountain, Iron Mountain [town], West Shasta Copper - Zinc District, Klamath Mts, Shasta Co., California, USA
|Latitude & Longitude (WGS84):||40° 40' North , 122° 31' West|
|Latitude & Longitude (decimal):||40.6666666667, -122.516666667|
A Cu-Zn-Fe-Pt-Ti-Cd-Au-Ag mine located in secs. 26, 27, 34 & 35, T33N, R6W, MDM, 0.7 km (2,300 feet) SE of Iron Mountain (town), 1.0 km (3,400 feet) SSE of Iron Mountain (summit) (coordinates of record), about 4 miles NNW of Kerwick and 9½ miles NW of Redding, on private land (mixed ownership ?). Discovery year was 1865. First year of production was 1879. Last year of production was 1962. Production years included 1897-1919, 1925, 1928-1930, 1943-1947, and the late 1950's to 1962. Owner-operator was Stauffer Chemical Co. and Iron Mountain Mines (1956-1977) (100.00%), California (1978). Owner was Iron Mountain Mines, Inc. (1985). MRDS database stated accuracy for this location is 10 to 100 meters.
Mineralization is a massive sulphide deposit (Deposit model: Model code 184; USGS model code 28a; name: Massive sulfide, kuroko; Mark3 model number 93), hosted in rhyolite. The deposit is comprised of several ore bodies, including: The Old Man; Hornet, Mattie, Richmond and Brick Flat ore bodies. Ore control was folds, a thick cover of shale (Early to Late Devonian), and pre-mineral faulting which may have provided channelways for mineralizing fluids. The primary mode of origin was hydrothermal and the secondary mode was contact metasomatism. There is moderate wallrock alteration (intermediate argillic; sericitic and pyritization, silicification of shale lies stratigraphically above the deposit. Mineralization is Early Devonian. Pyrite and chalcopyrite are found in approximately equal amounts. Local rocks include Paleozoic metavolcanic rocks, unit 1 (Eastern Klamath Mountains).
Regional Folds: Local major post-mineral faults are: Scott, Camden, and J Faults. The Camden also had pre-mineral movement. The Scott fault zone is 3-5 feett wide with many anastomosing slickensides and dark-gray to white gouge. The Scott is a normal fault, dipping 50NE, with a 250 foot dip-slip displacement. The Camden fault zone is 50 feet wide at the 2,600 foot level.
Workings included an open pit.
Assay analyses results: 1947: (1897-1947): 2-5% Zn, 2-7.5% Cu, 0.04-1 oz/ton Ag, 0.001-0.02 oz/ton Au.
Cumulative Cu production entries are for flotation plant. Copper ore of the Old Mine (Old Man ?) ore body, disseminated Cu.
Silver was discovered in gossan in 1879. The deposit was mined for sulphur during the late 1950'S to 1962. The Iron Mountains Mines, Inc. began engineering studies for a $20 million in-situ mining operation designed to recover Cu, Zn, and precious metals in 1985.
The iron which was mined was used in cement (all of it?). Pt was reported in smelter returns from Iron Mountain (Eilers (1913)).
Production and reserves data are found in: Kinkel et al (1956) Society of Economic Engineers field trip notes.
Mineral ListMineral list contains entries from the region specified including sub-localities
36 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Famennian - Emsian|
358.9 - 407.6 Ma
|Mesozoic granitic rocks, unit 4 (Klamath Mountains and Northern Sierra Nevada)|
Age: Devonian (358.9 - 407.6 Ma)
Stratigraphic Name: Bowman Lake Batholith; Wolf Creek Stock; Mule Mountain Stock
Comments: Plutons of Devonian age in northern Sierra Nevada and eastern Klamath Mts. Mostly granodiorite and trondhjemite coeval with associated island-arc volcanic rocks. Presumed to be Mesozoic at time of compilation of State geologic map
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
Localities in this Region
Hanks, Henry Garber (1884), Fourth report of the State Mineralogist: California Mining Bureau. Report 4, 410 pp. (includes catalog of minerals of California pp. 63-410), and miscellaneous observations on mineral products): 229.
Lang, Herbert (1899), Copper resources of California: Engineering & Mining Journal: 67: 561.
Aubury, Lewis E. (1902), The copper resources of California: California Mining Bureau Bulletin 23: 65.
Diller, J.S. (1903), Copper deposits of the Redding region, California: USGS Bulletin 213: 123-132; […(abstract): Geol. Zentralbl., Band 5: 394-395 (1904); …Engineering & Mining Journal: 77: 729 (1904)]: 126.
Eilers, A. (1913), Rare Metals in Blister Copper: American Institute of Mining Engineers Transactions: 47: 217-218.
Logan, Clarence August (1918), Platinum and allied metals in California: California Mining Bureau. Bulletin 85, 120 pp.: 93.
Laizure, Clyde McK (1921), Redding field division: California Mining Bureau. Report 17: 528.
Tucker, W. Burling (1924b), Copper resources of Shasta County: California Mining Bureau. Report 20: 427, 445.
Sosman, Robert Browning & E. Posnjak (1925), Ferromagnetic ferric oxide, artificial and natural: Journal of the Washington Academy of Science: 15: 332.
Newhouse, Walter Harry & J.P. Glass (1936), Some physical properties of certain iron oxides: Economic Geology: 31: 701.
Averill, Charles V. (1939), Mineral resources of Shasta County: California Journal of Mines and Geology, California Division of Mines (Report 35): 35: 127.
Palache, C., Berman, H. & Frondel, C. (1944), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume I: Elements, Sulfides, Sulfosalts, Oxides. John Wiley and Sons, Inc., New York. 7th edition, revised and enlarged, 834pp.: 644.
Huttl J.B. (1946), Diamond drilling features MT CU is Mining, Engineering and Mining Journal: 147(9): 64-68.
Eric, J.C. (1948), Tabulation of Copper Deposits of California, in: Copper in California: California Division of Mines Bulletin 144: 197-387.
Kinkel, Arthur Rudolph, Jr. & J.P. Albers (1951), Geology of the massive sulphide deposits at Iron Mountain, Shasta County, California: California Division Mines Special Report 14, 19pp.
Kinkel, Arthur Rudolph, Jr., Wayne E. Hall & J.P. Albers (1956) Geology and base metal deposits of west Shasta copper-zinc district, Shasta County, California: USGS PP 285, 156 pp.: 86, 89, 117-129 .
Kinkel, Arthur Rudolph, Jr., et al (1956), Society of Economic Geologists field trip notes.
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 130, 134, 156, 217, 241, 244, 247, 252, 302.
Clawson, R. F. (1969), Squaw Creek Copper Investigation: California Department of Water Resources Memoir Report, 29 p.
Clark, Wm. B. (1970a) Gold districts of California: California Division Mines & Geology Bulletin 193.
Moore, Lyman (1970), Copper Resources and Production of West Shasta Mining District, U.S. Bureau of Mines Report 85.
Lydon, Philip Andrew and O’Brien, J.C. (1974) Mines and mineral resources of Shasta County, California. California Division of Mines and Geology County Report 6, 154 pp.: 69, 152.
Hillman, C.T., Schumacher, O. and Gosling, B. (1977), The West Shasta County California, U.S. Bureau of Mines MAS Report, 40 pp.
Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 43, 73, 92, 98, 152, 162, 163, 174, 274.
Society of Economic Geologists (1984), Notes provided for Klamath Mountains field trip, October 7-13, 1984.
California Geology (1986), Mineral Industry of California, 1985: 39: 93.
California Division of Mines and Geology (1990), Mines and mineral producers active in California (1988-89), California Department of Conservation, Division of Mines and Geology, Special Publication 103.
Nordstrom, Darrell Kirk, Charles N. Alpers, Carol J. Ptacek, and David W. Blowes (2000), Negative pH and Extremely Acidic Mine Waters from Iron Mountain, California. Environmental Science & Technology: 34(2): 254-258.
USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10077593, 10189961 & 10216041.
Majzlan, J., Alpers, C. N., Koch, C. B., McCleskey, R. B., Myneni, S. C., & Neil, J. M. (2011). Vibrational, X-ray absorption, and Mössbauer spectra of sulfate minerals from the weathered massive sulfide deposit at Iron Mountain, California. Chemical Geology: 284(3): 296-305.
U.S. Bureau of Mines, Minerals Availability System (MAS) file ID #0060890368 & 0060890633.