Congress Mine (New Congress Mine; Congress Extension Mine; Malartic Hygrade; Queen of the Hills Mine; Niagara Mine; Herskowitz property; Golden Key; Fraction Patented 883; Piedmont; Mountain View; Homestake; Senate), Congress, Martinez District, Date Creek Mts, Yavapai Co., Arizona, USA
|Latitude & Longitude (WGS84):||34° 12' 3'' North , 112° 50' 58'' West|
|Latitude & Longitude (decimal):||34.20083,-112.84944|
|Köppen climate type:||BSk : Cold semi-arid (steppe) climate|
‡Ref.: Report of the Governor of Arizona (1899): 54-56.
Engineering and Mining Journal (1904), The Silvebell Camp, Arizona: 77: 639.
Wilson, E.D., et al (1934), Arizona Lode Gold Mines and Gold Mining. Arizona Bureau of Mines Bull. 137: 69-73.
Metzger, O.H. (1938), Gold Mining and Milling in the Wickenburg Area, Maricopa and Yavapai Counties, Arizona: US Bureau of Mines Information Circular 6991: 45.
Niemuth, N.J. (1987), Arizona Mineral Development 1984-1986, Arizona Department of Mines & Mineral Resources Directory 29, 46pp.
Rocks & Minerals: 64: 300.
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.: 290.
Arizona Department of Mineral Resources Niagara Mine and MIll file.
Arizona Department of Mineral Resources Congress Mine file.
Arizona Department of Mineral Resources Golden Key file.
U.S. Bureau of Land Management Mining District Sheets 309 & 310.
USGS Congress Quadrangle map.
MRDS database Dep. ID #10027544, MRDS ID #M003323; and, Dep. ID #10234784, MRDS ID #M001105, MAS ID #0040250537; Dep. ID #10283404, MAS ID #0040250534 and, Dep. ID #10234633, MAS ID #M001105.
A former underground Ag-Au-Cu-Pb-U mine located 3 miles NW of Congress Junction at an altitude of 3,400 feet. Discovered by Dennis May about 1887 and sold to Joseph "Diamond Jo" Reynolds for $65,000, who opened the mine. It closed and reopened March, 1889 and ultimately closed August 1891 (Reynold's death). Reopened again March 1894 to the end of 1910. Land also in sections 13-15 & 23. Also known as/designated: Congress Mine Patented claim 878.
Mineralization is ore in flat lenses and pinch-and-swell bodies. Ore control was faulting, shearing and igneous activity. Ore concentration was oxidation at near surface. No alteration noted.
Host rocks consist essentially of coarse-grained biotite granite, intruded by aplite, pegmatite and greenstone dikes. Mineralization consists of several major veins: Congress vein; Niagara vein; and, the Queen of the Hills vein. These occur within fault fissures which strike generally westward and dip northward.
The Congress fissure occurs largely in a greenstone dike about 15 feet (5 meters) thick. The filling is coarse-textured, massive, grayish-white quartz with irregular masses, bands & disseminations of fine-grained iron sulfide. Ore zones are generally flat lenses near the footwall. The longest of the 650 level was about 1,800 feet long and averaged less than 3 feet thick.
The Niagara vein goes down 2,000 feet and has small amounts of galena and a higher silver content.
Area structures include granite that is massive and unfoliated. Veins parallel andesite dikes which trend E-W to NE and dip at low angles, less than 40 degrees.
Workings include 7 shafts, all sunk on inclines. Three were on the Congress vein: (No. 1 (1,100 feet); No. 2 shaft (1,700 feet); No.3 (4,000 feet). 3 shafts were sunk on the Niagara vein: No. 4 (1,000 feet); No. 5 (2,050 feet); No. 6 (1,800 feet). One shaft was sunk on the Queen and Hills vein to a depth of 200 feet below the tunnel level. These shafts were sunk at an approximate incline of 25º from the horizontal. A 20-stamp mill with Frue-vanner table for concentrating, and later, a 40-stamp mill and additional vanner tables were added.
Production was some 687,542 tons of ore milled yielding 388,477 oz. Au and 345,598 oz. Ag.
6 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
|Quaternary - Miocene|
0 - 23.03 Ma
|Cenozoic sedimentary rocks|
Age: Cenozoic (0 - 23.03 Ma)
Lithology: Sedimentary rocks
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. 
1400 - 1600 Ma
|Middle Proterozoic granitic rocks|
Age: Calymmian (1400 - 1600 Ma)
Description: Mostly porphyritic biotite granite with large microcline phenocrysts, with local fine-grained border phases and aplite. Associated pegmatite and quartz veins are rare. This unit forms large plutons, including the Oracle Granite, Ruin Granite, granite in the Pinnacle Peak - Carefree area northeast of Phoenix, and several bodies west of Prescott. (1400-1450 Ma)
Comments: ~ 1.4 Ga
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.