Iron King Mine (Lime Rock Patented claim 1714; Copper Platter Patented claim 1714; Patented claims 1714), Humboldt, Big Bug District, Prescott quadrangle, Bradshaw Mts (Bradshaw Range), Yavapai Co., Arizona, USA
Latitude: 34°30'3"N
Longitude: 112°15'24"W
‡Ref.: Lindgren, W. (1926), USGS Bull. 782: 37, 127-128.
Wilson, E.D., et al (1934), AZ Bur. Mines Bull. 137: 36.
Kumke, C.A. and Mille, H.F. (1950) Mining Methods and Practices at the Iron King Mine. U.S. Bureau of Mines Information Circular 7539.
Wilson, E.D., et al (1950), Arizona zinc and lead deposits, part I, Arizona Bureau of Mines Bull. 112-122. 156.
Creasey, S.C. (1952), Geology of the Iron King Mine, Yavapai County, Arizona, Economic Geology: 47(1): 24-56.
Anderson, C.A. & S.C. Creasey (1958), Geology and ore deposits of the Jerome area, Yavapai County, Arizona, USGS PP 308: 91, 92, 155-169.
Galbraith, F.W. & D.J. Brennan (1959), Minerals of Arizona: 102.
Krieger, M.H. (1965), Geology of the Prescott and Paulden quadrangles, Arizona, USGS PP 467: 104, 105, 109-110.
Moxham, R.M., et al (1965), Gamma-ray spectrometer studies of hydrothermally altered rocks, Economic Geology: 60: 653-671.
Gilmour, P. and Still (1968) in: Ore Deposits of the United States, Graton-Sales Volume, Vol. II: 1238-1257.
Koschmann, A.H. and Bergendahl, M.H. (1968) Principal Gold Producing Districts of the United States. USGS PP 610: 46.
Anderson, C.A. & P.M. Blacet (1972), Precambrian geology of the northern Bradshaw Mountains, Yavapai County, Arizona, USGS Bull. 1336: 72.
Niemuth, N.J. (1987), Arizona Mineral Development 1984-1986, Arizona Department of Mines & Mineral Resources Directory 29, 46pp.
Mining Record (1990) June 6, 1990: 45.
Sawyer, M.B., Gurmendi, A.C., Daley, M.R., and Howell, S.B. (1992) Principal Deposits of Strategic and Critical Minerals in Arizona, U.S. Bureau of Mines Special Publication, 334 pp.
Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 112, 114, 117, 120, 122, 159, 167, 179, 215, 229, 309, 317, 378, 391, 401.
U.S. Bureau of Mines - Arizona Bureau of Geology and Mining Technology file data.
USGS Prescott Valley South Quadrangle map.
Arizona Department of Mineral Resources Geology File Big Bug District General Report.
Arizona Department of Mineral Resources Iron King Mine file.
U.S. Bureau of Land Management Mining District Sheets 18 & 19.
MRDS database Dep. ID #10027180, MRDS ID #M002386; and, Dep. ID #10186749, MAS ID #0040251180.
A former underground Au-Ag-Cu-Pb-Zn-Cd mine located in sec. 21, T.13N., R.1E., on the NE slopes of the Bradshaw Mountains, about 12 miles east of Prescott, and about 1 mile SW of Humboldt. Discovered 1880 and started production 1903. Started 1906-07 & closed. Reopened for WWI and ultimately closed December 1, 1968. Owned at times, or in part by, the Southwest Metals Co. (1926- ); Fred Gibbs (Iron King Mining Co.)(1936-1937). Shattuck Denn Corp. purchased the property in 1942 & operated it until January 1, 1968; subsequently, McFarland.& Hollinger took over the property and resumed operations until ultimate closure. Claims extend into the W½SW¼ of sec. 15, the W½NW¼NW¼ of sec. 22, the E½ and E½W½ of sec. 21, and the NE¼NW¼NE¼ of sec. 28.
Mineralization is en echelon veins, arcuate.
Precambrian rocks are widespread in the district and are represented most abundantly by the Yavapai schist, a series of metamorphosed sedimentary rocks, partly tuffaceous, and related flows. Intrusive rocks, also of Precambrian age, are common in the schist and range in composition from granite to gabbro.
In the Iron King and adjacent areas, faults and a pronounced foliation are the dominant structures. Regional mapping revealed several isoclinal folds, whose magnitudes are measureable in hundreds of feet, several miles to the east of the mine, but none was recognized in the mine area.
The Iron King area is underlain by the Yavapai schist which has been sudivided into meta-andesite flows, meta-andesite tuffs, metarhyolite tuff and conglomerate, and hydrothermally altered rocks formed prior to and at the time of ore deposition. Quaternary gravels overlie the Yavapai schist.
The meta-andesite flows consist of a green rock of uniform granularity containing relic plagioclase phenocrysts in a chloritic groundmass. Granules of epidote are common, and in some localities the rock is amygdaloidal. Foliation is well developed, but not so prominently as in some of the metatuffs.
The meta-andesite tuffs are fine- to medium-grained rocks which locally show bedding. The dominant megascopic constituents are chlorite, saussuritized feldspar, and quartz in variable amounts. The finer-grained facies is composed largely of chlorite, being essentially a chlorite-phylliten, in which the foliation is very well developed. The alteration and mineralization is a deposit in these andesitic tuffaceous rocks of the upper unit of the Spud Mountain volcanics. The deposit is a replacement zone in Yavapai Schist. A series of lenses, in part overlapping, in highly silicified schist.
The dominant structural features in the Iron King area are regional foliation striking N.15º to 30ºE. and dipping 70º to 85º NW., and the fault zones occupied by the Iron King veins with accompanying alteration zone. The foliation is well developed in the metamorphic rocks throughout the area but is more prominent in zones of fine-grained material. The attitude of the foliation varies locally and is both parallel to, and at a slight angle to, the bedding. The foliation is cut in places by south-dipping slip planes striking NE and NW.
The altered shear zone occupied by the Iron King deposit strikes about N.25ºE., generally parallel to the foliation. It represents two periods of shearing. The earier period localized the early minerals characterizing the hydrothermal alteration zone. The second period brecciated the early minerals and permitted introducton of the ore-forming minerals.
Younger reverse faults recognized in the mine have offset the vein, but the displacement on them is not great, the maximum vertical displacement being from 80 to 100 feet. Displacement on these faults diminishes rapidly along the strike. Where the reverse faults are less steep than the vein, they have produced a gap or separation of the vein; and where they are steeper, an overlap has resulted.
The deposit is a massive sulphide replacement of schist along well defined veins which have sharp contacts with the wall rocks. The host rock within the veins is nearly completely replaced.
The entire ore deposit consisted of 12 veins (lenses) arranged en echelon. Each vein extends further to the North than the adjacent vein on the East. The North end of the veins plunge Northward. The width of each vein ranges from 1 to 14 feet and lengths are 150 to 500 feet long. The entire mineralized zone is 75 feet wide. The strike is N.21ºE. and dips 75ºW. Veins consist of fine-grained, massive sulfides held together by a gangue of ankerite, quartz, sericite and residual chlorite. The ore is steel-gray, flinty schist containing a crushed quartz mosaic of coarser and finer grains, intergrown with some dolomitic carbonate and tourmaline. The North end of the veins are almost exclusively quartz.
All of the veins are zoned and all in a similar manner. The north end of each one consists of massive quartz having sparse pyritic disseminations and ramifying veinlets. The quartz is commonly fine-grained, compact, gray to greenish in color, and almost chalcedonic in appearance. Locally, white bull quartz is associated as irregular patches or as veinlike masses cutting the finer-grained type. The quartz has a sharp contact with the massive sulphide. This contact trends obliquely across the vein in a northerly direction and is more nearly vertical than the vein in cross section. In places the quartz contains sufficient gold and silver to be ore, and it may have a slight concentration of more granular galena near the contact with massive sulphides.
South of the quartz the veins are massive sulphide in which sphalerite and galena are the dominant ore minerals. The highest content of sphalerite plus galena commonly occurs some distance south of the quartz zone. Closely spaced assays show that in each of several veins the zone of higher lead and zinc content begins as a narrow stringer on the footwall of the vein and gradually migrates northward to the hanging wall, duplicatng the pattern of the transition to the quartz masses at the north ends of the veins. In general, from the quartz southward the content of galena and sphalerite increases gradually to a maximum and then decreases gradually farther toward the south. There is a complimentary increase in pyrite content toward the south as the Pb & Zn content decreases. The pyrite at the south end of the veins is more granular and commonly has a characteristic cubic form. Farther south, the massive sulphide character of the veins grades into zones of quartz-pyrite stringers separated by thin schist partings containing granular, disseminated pyrite.
There are no major changes of the veins in depth. The zoning is similar in each vein on all levels, and the mineralogical and structural character of the veins is about the same on the upper and lower levels. However, the Pb-Zn content of several of the more easterly veins diminishes on the 700 and 800 levels, but may increase with greater depth as in several of the other veins.
Workings included 2 shafts 750 feet apart at 435 feet and 225 feet deep, respectively; later, 7 shafts. Shafts 6 and 7 were hoisting shafts. The earlier shafts were used for ventilation (Nos. 1 & 5), emergency exits (No. 2) or were caved (Nos. 3 & 4). The No. 6 shaft is a two-compartment shaft which extends below the 1200 level and was the primary working shaft. There were eleven levels, extending to about 1,140 feet below the collar of the shaft. The overall mining operation was some 2,600 feet deep vertically. Production was 3,933 pounds of Cu, 1,253 az Au & 35,491 oz. Ag (1906-07); and, 616,493 oz Au, 18,494,491 oz. Ag, 125,375 tons Pb, 367,569 tons Zn, and 9,551 tons Cu (1907-1964).
Mineral List
24 entries listed. 17 valid minerals.
The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please
register so you can add to our database. This locality information is for reference purposes only. You should never attempt to
visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders
for access and that you are aware of all safety precautions necessary.
Mineral and Locality Search
