Ruby Mine (Mineral Mountain), Forest, Alleghany District (Forest District), Sierra Co., California, USA
|Latitude & Longitude (WGS84):||39° 31' 7'' North , 120° 50' 43'' West|
|Latitude & Longitude (decimal):||39.51861,-120.84528|
|Köppen climate type:||Csb : Warm-summer Mediterranean climate|
A former lode (?) Au occurrence/mine located in secs. 10, 11, 14 & 15, T19N, R10E, MDM, 3.1 km (1.9 miles) NNE of Forest, N of Table Mountain, and about 3¼ miles N of Alleghany, on National Forest land. Owned & operated by the Brush Creek Mining and Development Co. (100%), California (1992). MRDS database stated accuracy for this location is 100 meters. This mine was closed in 1942 by the War Production Board, but was reopened in 1992. Main workings, including adit, are in sec. 15. Other locations in adjacent sections.
NOTE: USGS MRDS database file #10188969 apparently also pertains to this mine; however, it presents geographic coordinates placing the locality in proximity of Alleghany proper in sec. 34 (-120.84413, 39.47049)of the same T&R. This file has a single reference (an unspecified MESA file) and otherwise presents a paucity of data. The other 2 MRDS files agree with the topo map that this mine is centered in sec. 15 (named mine on the topo).
The coarse gold nuggets recovered at the mine are among the finest specimens in the world, company officials said.
Local rocks include Tertiary pyroclastic and volcanic mudflow deposits, unit 9 (Cascade Range).
Workings include unspecified underground openings (topo map shows a single adit symbol).
Prior to the 1942 closures, this mine produced more than 5,600 kilograms (180,000 Troy ounces) of Au.
Reserve-Resource data are found in: Randol Mining Directory 1996/1997: 166.
Reserves and resources information: Type: in-situ (estimate year = 1996); total resources set at 2,970,000 metric tons of ore; Au = 6.9 grams/metric ton.
1 valid mineral.
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
|Gelasian - Chattian|
1.806 - 28.1 Ma
|Tertiary pyroclastic and volcanic mudflow deposits, unit 9 (Cascade Range)|
Age: Cenozoic (1.806 - 28.1 Ma)
Stratigraphic Name: Alturas Formation; Bonta Formation; Cedarville Series (part); Delleker Formation; Ingalls Formation; Mehrten Formation (part); Nomlaki Tuff Member; Penman Formation; Reeds Creek Andesite; Spanish Canyon Formation; Tropico Group (part); Tuscan Formation; Valley Springs Formation (part)
Description: Tertiary pyroclastic and volcanic mudflow deposits.
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. 
Ferguson, Henry G. & R.W. Gannett (1932), Gold quartz veins of the Alleghany district, California: USGS Professional Paper 172.
Carlson, D.W. & W.B. Clark (1956), Lode gold mines of the Alleghany-Downieville area, Sierra County, California: California Journal of Mines and Geology: 52: 237-291.
Clark, Wm. B. (1970a) Gold districts of California: California Division Mines & Geology Bulletin 193: 19.
Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 32.
Lucas, J.M. and Roberto, M. (1992), U.S. Bureau of Mines Minerals Today (October, 1992): 29.
The Mining Record (1993): 104(28) (7-14-93): 1.
The Mining Record (1993): 104(41) (10-13-93): 1.
The Mining Record (1993): 104(46) (11-17-93): 5.
California Division of Mines and Geology, Mine File Database, June 1993.
Mining Journal(1993): 321: 402.
The Mining Record (1994): 105(17) (4-27-94): 6.
Randol Mining Directory (1996-1997), U.S. Mines and Mining Companies: 166.
USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10077640, 10188969 & 10286771.
U.S. Bureau of Mines, Minerals Availability System (MAS) file #0060910193 & 0060910652.