Central Eureka

The Central Eureka is a gold and silver mine located in Amador county, California.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

Satelite View

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Site Name

Primary: Central Eureka

Commodity

Primary: Gold
Primary: Silver
Tertiary: Iron
Tertiary: Zinc
Tertiary: Lead
Tertiary: Copper

Location

State: California
County: Amador

Land Status

Land ownership: Private
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

Holdings

Not available

Workings

Not available

Ownership

Owner Name: Central Eureka Mining Co.

Production

Not available

Deposit

Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Discovery Year: 1855
Years of Production:
Organization:
Significant: N
Deposit Size: L

Physiography

General Physiographic Area: Pacific Mountain System
Physiographic Province: Cascade-Sierra Mountains
Physiographic Section: Sierra Nevada

Mineral Deposit Model

Not available

Orebody

Form: TABULAR/PINCH AND SWELL

Structure

Not available

Alterations

Alteration Type: L
Alteration Text: Hydrothermal Alteration Of Meta-Andesite Causing Blocky Meta-Andesite To Mix With Quartz In Ore Veins; Meta-Andesite Altered To Schist In Places.

Rocks

Not available

Analytical Data

Not available

Materials

Ore: Pyrite
Ore: Gold
Ore: Sphalerite
Ore: Chalcopyrite
Ore: Galena
Ore: Silver
Gangue: Quartz
Gangue: Albite
Gangue: Ankerite

Comments

Comment (Commodity): GOLD ALLOYED WITH SILVER IN FREE-MILLING STATE OR GOLD DISSEMINATED WITH PYRITE; PYRITE AND ARSENOPYRITE COMMON, SPHALERITE, CHALCOPYRITE AND GALENA MINOR.

Comment (Location): SW 1/4

Comment (Workings): 2 INCLINED SHAFTS AVERAGING 65 DEGREES 4855 AND 3500 FT.; 3500 FT. SHAFT WITH WINZE AT BASE TO 4150 FT., WATER CONFINED TO THIS SHAFT; LEVELS AT 2900 , 3100 , 3400 , 3500 , 3600 , 3700 , 3800 , 3900 , 4150 , FT. WITH TOTAL OF SEVERAL THOUSAND FT. OF DRIFTS; DUE TO CONSIDERABLE GOUGE ON WALLS OF MOST LEVELS, STOPES TIMBERED CLOSE TO FACE; CUT AND FILL METHOD OF STOPING USED.

Comment (Geology): GEOL.DESC: ORE BODIES CONSIST OF QUARTZ-ANKERITE-ALBITE AND MASSIVE QUARTZ STRINGERS, LENSES AND VEINS. IN UPPER PORTION OF MINE ORE BODIES IN BLACK SLATE AT CONTACT WITH META-ANDESITE; META-ANDESITE HANGING WALL BUT BOTH IT AND SLATE FOUND ON BOTH WALLS DUE TO VEINS CROSSING INTERBEDDED LENSES OF BOTH ROCK TYPES. ORE VEIN AT DEPTH IS A BLACK GOUGE WITH QUARTZ STRINGERS. AVERAGE THICKNESS OF MINERALIZED BLACK GOUGE ZONE 8 FT. ONE ORE BODY PARALLEL TO ORE VEIN 420 FT. LONG, 280 FT. WIDE; LARGE WEDGE 850 FT. LONG, 35 FT. WIDE AND AS GREAT AS 125 FT. CONTAINS SEVERAL ORE LENSES.

Comment (Deposit): OLD EUREKA MINE INCORPERATED WITH CENTRAL EUREKA MINE; BOTH OPERATED SEPARATELY UNTIL 1924 WHEN THEY MERGED.

Comment (Deposit): Discovery Year: 1850'S

Comment (Production): CENTRAL EUREKA , ORIGINALLY "SUMMIT" WORKED FROM 1855-1875; REOPENED IN 1895 AS CENTRAL EUREKA; OPERATED INTERMITTENTLY UNTIL 1924 WHEN CONSOLIDATED WITH OLD EUREKA WHICH HAD BEEN WORKED INTERMITTENTLY SINCE 1852. WORKED INTERMITTENTLY FROM 1930 TO 1942; MINING RESUMED IN 1946 BUT LITTLE DONE UNTIL 1948. PRODUCED 39,440 TONS OF ORE YIELDING MORE THAN $500,000 IN GOLD AND SILVER IN 1951. TOTAL PRODUCTION (BOTH MINES) $36,000,000 APPROX. TO END OF 1951. GOLD ALLOYED WITH SILVER IN FREE-MILLING STATE OR DISSEMINATED IN PYRITE, PYRITE AND ARSENOPYRITE ARE COMMON, SPHALERITE, CHALCOPYRITE, AND GALENA ARE PRESENT IN MINOR AMOUNTS

References

Reference (Deposit): CARLSON, D.W. AND CLARK, W.B., 1954 , MINES AND MIN. RES. OF AMADOR COUNTY, CAL.: CJMG VOL. 50 , P. 173

Reference (Deposit): LOGAN, C.A., 1934 , MOTHER LODE GOLD BELT OF CAL.: CBM BULL. 108 , P. 74 - 80 .

Reference (Deposit): USGS PROF. PAPER 157, P. 59-62

Reference (Production): CARLSON, D.W. AND CLARK, W.B., 1954

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.