Great Western

Site Name

Primary: Great Western
Secondary: Great Western Quicksilver Mine
Secondary: Laguna Western

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Commodity

Primary: Mercury
Secondary: Chromium

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Location

State: California
County: Lake
District: East Mayacmas

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Land Status

Not available

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Holdings

Not available

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Workings

Type: Surface/Underground

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Ownership

Owner Name: Westfall Mining Co.
Years: 1970 -

Owner Name: Bradley Mining Co.
Years: 1965 -

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Production

Year: 1962
Time Period: To 1962
Material type: HG. [Production info from USBM data.]
Description: Cp_Grade: ^5-15 Lb/Ton

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Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Surface-Underground
Year First Production: 1873
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: Y
Deposit Size: M

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Physiography

General Physiographic Area: Pacific Mountain System
Physiographic Province: Pacific Border Province
Physiographic Section: California Coast Ranges

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Mineral Deposit Model

Not available

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Orebody

Form: PIPES

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Structure

Type: R
Description: Mayacmas Anticline Trending Nw

Type: L
Description: Lithologic Contacts

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Alterations

Alteration Type: L
Alteration Text: Silica Carbonate Alteration Of Serpentine, Kaolinized Sediments

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Rocks

Name: Gabbro
Role: Associated
Age Type: Host Rock Unit
Age Young: Late Cretaceous

Name: Gabbro
Role: Associated
Age Type: Host Rock
Age Young: Late Jurassic

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Analytical Data

Not available

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Materials

Ore: Cinnabar
Gangue: Opal
Gangue: Calcite
Gangue: Pyrite
Gangue: Quartz
Gangue: Dolomite

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Comments

Comment (General): From the caption of a photograph for sale on Ebay as of 08-nov-2010: GREAT WESTERN QUICKSILVER MINING CAMP LAKE COUNTY, CALIFORNIA Circa 1880. No photographer's imprint. photo measures 4.75 x 3.5 inches, mounted on 9.25 x 7.25 inch card board, in very good condition. As gold prospecting moved from nuggets in streams to underground mining, mercury had to be produced in large quantities. One of the main sources of mercury was the Great Western Quicksilver Mine in Lake County. It became one of the most important and longest producing mercury mines in California between 1875 and 1900.

Comment (Location): LOCATED AT CORNER OF SECTIONS 16, 21, 22.

Comment (Workings): WORKINGS HAVE CAVED

Comment (General): From http://www.calarchives4u.com/history/history-lake.htm California Genealogy and History Archives Lake County History A Memorial and Biographical History of Northern California Chicago, Lewis Publ. Co., 1891 The Great Western mine, which has been worked since 1856, is located four miles south of Middletown. The claim covers six thousand linear feet on the vein, which strikes east and west, and dips to the south at an angle of sixty-five degrees. The hanging-wall is clay-slate, quite soft near the vein; the foot-wall is serpentine. In the first instance the mine was opened by and worked through a tunnel two thousand two hundred feet long, intersecting the vein at a depth of two hundred and nineteen feet. Work is now carried on through a shaft three hundred and fifty feet deep. Both shaft and tunnel are thoroughly timbered. For ore hoisting a ten by eighteen-inch double spur-geared reversible hoist is used. For handling the water a No. 6 Dean steam pump, with two one and one half-inch columns, is employed. The ore is cinnabar, the fine being worked in a twelve-ton Knox & Osborn furnace; the coarse in a thirty-ton Green furnace. For creating draft in the condensers, blowers driven by a six by eight-inch horizontal engine are employed. Water is brought on the premises through two miles of flume and three-fourths of a mile of piping. Six cords of wood are consumed daily ?three for steam purposes and three in the furnaces. About two hundred pounds of Safety Nitro powder are used every ninety days. The company employs thirty men in the mine, and fifteen in the reduction works, the white men receiving $3 per day and the Chinese $1.15.

Comment (General): From http://pontdechevalier.com/knights-valley/ [as of 08-nov-2010] Between 1875 and 1900 the Great Western Quicksilver Mine Company, located on the border of Sonoma and Lake Counties, became the most important mercury producing mine in California. At its peak, the mine shipped between 27,000 and 31,500 tons of mercury per year to be used in gold mining operations. Located some 45 miles outside Calistoga, the mine transported the quicksilver by horse-drawn wagon over rough mountain roads, which sometimes took an entire week of rough travel to reach Calistoga. There, it was shipped by rail to San Francisco.

Comment (Location): Deleted duplicate record MAS 0060330056 (newMRDS 10139180) placed coordinates at the Maypole mine. Coordinates given are for the old MRDS location in Secs. 16, 21, 22. There appears to be ground disturbance in this area on Google Earth imagery.

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References

Reference (Deposit): 1960 DIREXPL UNIVERSAL SILVER

Reference (Deposit): U.S. BUREAU OF INDIAN AFFAIRS, 1979, ADMINISTRATIVE REPORT BIA-49, 85 p.

Reference (Deposit): AVERILL, C.V., 1947, MINES AND MINERAL RESOURCES OF LAKE COUNTY, CALIF.: CJMG, V. 43, no. 1, P. 15-38
Pages: p. 27-28.

Reference (Deposit): BRADLEY, W. W., 1918, QUICKSILVER RESOURCES OF CALIFORNIA: CALIF. STATE MINING BUREAU BULL. 78, 389 P.

Reference (Deposit): RANSOME, A. L. AND KELLOGG, J. L., 1939, QUICKSILVER RESOURCES OF CALIFORNIA: CALIF. JOUR. OF MINES AND GEOLOGY, V. 35, P. 353 - 486

Reference (Deposit): YATES, R. G. AND HILPERT, L. S., 1946, QUICKSILVER DEPOSITS OF THE EASTERN MAYACMAS DISTRICT, LAKE AND NAPA COUNTIES, CALIFORNIA: CALIF. JOUR. OF MINES AND GEOLOGY, V. 12, P. 231 - 286

Reference (Deposit): BAILEY, E. H., USGS, PERSONAL FILES

Reference (Deposit): HOLMES, G. W., JR., 1965, MERCURY IN CALIFORNIA: IN USBM IC 8252

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California Gold

"Where to Find Gold in California" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in California. Read more: Where to Find Gold in California.