Octave Mine (Joker Mine; Bonanza Mine), Octave, Weaver District (Virginia District; Mocking Bird District), Weaver Mts, Yavapai Co., Arizona, USA
|Latitude & Longitude (WGS84):||34° 8' 38'' North , 112° 42' 24'' West|
|Latitude & Longitude (decimal):||34.14389,-112.70667|
|Köppen climate type:||BSk : Cold semi-arid (steppe) climate|
A former underground Au-Cu-Ag-Pb-Zn mine located at Octave, SW base of the Weaver Mountains at 3,300 feet of altitude. Started about 1860's (1865 ?). Reopened 1900-1905. Owned by the Octave Gold Mining Co. (to ultimate closure in 1912). Reopened again in 1908 by the Octave Mines Co. which developed the "Joker workings" until 1922. Finally, reopened in 1922 by Arizona Eastern Gold Mines Co., Inc. until 1930.
This mine is on a pediment. The pediment and mountains immediately NE of Octave consist mainly of grayish quartz diorite with included lenses of schist and NE-ward trending dikes of pegmatite, aplite and altered, fine-grained basic rock (altered diabase).
Mineralization is the Octave vein which occurs within a fault fissure that strikes N.70ºE. and dips from 20º to 30ºNW. It is several thousand feet along trace and intersected by 3 or 4 systems of post-vein faults of generally less than 100 feet of displacement. Filling consists of coarse-textured, massive to laminated, grayish-white quartz with irregular masses, disseminations and bands of sulfides. Vein is a few inches to 5 feet wide and averages 2¼ feet (67.5 cm) wide. In places it narrows abruptly and forms branching stringers.
There is a smaller vein about 25 feet from the main vein. The wall rocks are sericitized, silicified and carbonitized.
Two orebodies were found below the 600 level. The larger was followed for a horizontal distance of about 700 feet by a maximum height of 200 feet.
Area structures include veins parallel to mafic dikes which trend NE and dip at low angles, usually less than 40 degrees. Foliation in Precambrian metamorphic rocks trends N10E to N25E. The granitic rocks are unfoliated.
Mined to a depth of 2,000 feet on incline (1900-1905) plus 2,000 feet along strike. The Joker shaft is 1,250 feet deep on incline. This shaft connects with a few thousand feet of drifts. The old Octave workings included 4 shafts and several thousand feet of drifts and extensive stopes on 3 oreshoots.
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
1600 - 1800 Ma
|Early Proterozoic metasedimentary rocks|
Age: Statherian (1600 - 1800 Ma)
Description: Metasedimentary rocks, mostly derived from sandstone and shale, with minor conglomerate and carbonate rock. Includes quartz-rich, mostly nonvolcanic Pinal Schist in southeastern Arizona and variably volcanic-lithic sedimentary rocks in the Yavapai and Tonto Basin supergroups in central Arizona. (1600-1800 Ma)
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. 
Elsing, M.J. and Heineman, E.S. (1936) Arizona Metal Production, Arizona Bureau of Mines Bulletin 140: 103.
Wilson, E.D. (1938), Arizona Bureau of Mines Bull. 145: 130-132.
Mine start file. Arizona State Mine Inspectors Office (1979).
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.
USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10027632 & 10283260.
U.S. Bureau of Mines, Minerals Availability System (MAS) file ID #0040250935.
Arizona Department of Mineral Resources Octave file.
U.S. Bureau of Mines - Arizona Bureau of Geology and Mining Technology file data.
USGS Yarnell Quadrangle map.