Darwin Group

The Darwin Group is a lead, zinc, and silver mine located in Inyo 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

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Darwin Group
Secondary: Bernon
Secondary: Columbia
Secondary: Defiance Driver
Secondary: Essex
Secondary: Independence
Secondary: Lane
Secondary: Liberty
Secondary: Lucky Jim
Secondary: Promontory
Secondary: Rip Van Winkle
Secondary: Southwest and Thompson.

Commodity

Primary: Lead
Primary: Zinc
Primary: Silver
Secondary: Gold
Secondary: Tungsten
Secondary: Copper

Location

State: California
County: Inyo
District: Darwin

Land Status

Not available

Holdings

Not available

Workings

Not available

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Years of Production:
Organization:
Significant: N
Deposit Size: M

Physiography

Not available

Mineral Deposit Model

Model Name: Polymetallic replacement

Orebody

Form: IRREGULAR

Structure

Type: R
Description: Thrust Fault, Igneous Intrusions

Type: L
Description: Faults, Folds

Alterations

Not available

Rocks

Name: Quartz Monzonite
Role: Associated
Age Type: Associated Rock
Age Young: Late Cretaceous

Analytical Data

Not available

Materials

Ore: Pyrite
Ore: Tetrahedrite
Ore: Chalcopyrite
Ore: Sphalerite
Gangue: Fluorite
Gangue: Iron
Gangue: Jarosite
Gangue: Clay
Gangue: Gypsum
Gangue: Calcite
Gangue: Quartz
Gangue: Jasper

Comments

Comment (Production): PRODUCTION RECORD NOT COMPLETE, 1941 - 1943 , 28,400 TONS OF ORE WAS MINED, 17,000 TONS WAS SHIPPED, AVERAGING 9 % PB, 4 % ZN. 1957 INFORMATION; PRODUCTION IN RECENT YEARS HAS BEEN 8,000 - 10,000 TONS PER MONTH, REDUCED TO 20 % OF ORIGINAL VOLUME BY MILLING AND FLOATATION. MILL HEADS HAVE AVERAGED 6 OZ. AG, 6.5 % PB, 6.4 % ZN, SOME GOLD. BEFORE ANACONDA OPERATIONS, ESTIMATED PRODUCTION IS $7,000,000 . COPPER AND TUNGSTEN AS BY - PRODUCTS. ANACONDA PRODUCES, 8,000 TONS PER MONTH.

Comment (Deposit): THREE TYPES OF ORE BODIES ARE RECOGNIZED: REPLACEMENTS OF SILICIFIED LIMESTONE, BEDDING REPLACEMENT, AND FISSURE FILLING.

Comment (Workings): UNDERGROUND WORKINGS TOTAL SEVERAL MILES IN LENGTH, NEW WORKINGS ARE ADVANCED AT RATE OF 7,000 FT/YEAR. 45 PATENTED CLAIMS AND 44 UNPATENTED CLAIMS

Comment (Commodity): CLOSED (TEMPORARILY) BY ECONOMIC CONDITIONS IN 1957, BUT A VERY IMPORTANT DISTRICT IN RECENT YEARS, CHIEF PRODUCTION SINCE 1945 WAS LEAD, ZINC, AND SILVER WITH SOME COPPER. (MC KNIGHT, 1960?, UNPUBLISHED DATA.)

Comment (Geology): DEPOSITS ARE MESOTHERMAL REPLACEMENT BODIES IN LIME SILICATE CONTACT METAMORPHIC ROCK (PENNSYLVANIAN), ALONG AND NEAR STRIKE SLIP FAULTS, BELOW A MAJOR THRUST FAULT, AND ADJACENT TO IGNEOUS STOCK; PARTLY IN IRREGULAR PIPES. SMALL STOCK OF QUARTZ MONZONITE AND GRANODIORITE, SILL OF QUARTZ MONZONITE, DIKES OF APLITE, AGE PROBABLY CRETACEOUS. (MC KNIGHT, 1960?, UNPUBLISHED DATA.) ; GEOL.DESC: DEPOSITS; IN A THICK SERIES OF PALEOZOIC LIMESTONE, DOLOMITE, SHALE AND QUARTZITE WHICH IS FOLDED AND FAULTED. PRINCIPAL STRUCTURE IS NW - PITCHING ANTICLINAL FOLD, EAST FLANK OF FOLD IS INTRUDED BY DARWIN GRANODIORITE STOCK AND ASSOCIATED DIKES AND SILLS WHICH GRADE FROM GRANITE TO GABBRO. PERIPHERAL TO STOCK IS A 2500 FT. WIDE ZONE OF TACTITE. ALL MINERALIZATION RELATED TO STOCK. SEDIMENTARY SERIES INTRUDED ON THE WEST AND SOUTH BY COSO GRANITE BATHOLITE. LARGEST FAULT IS THE DARWIN TEAR FAULT, STRIKES N 60 - 75 W, DIPS STEEPLY SOUTH, TRACEABLE FOR 10 MILES.

References

Reference (Deposit): GOODWIN, J. C., 1957 , LEAD AND ZINC IN CALIFORNIA; CALIF. JOUR. MINES AND GEOLOGY VOL. 53 , NO. 3 & 4 ; DIV. OF MINES, P. 466

Reference (Deposit): HALL, W. E. AND MACKEVETT, E. M., 1958 , ECONOMIC GEOLOGY OF THE DARWIN QUADRANGLE, INYO COUNTY, CALIFORNIA; DIV. OF MINES SPEC. REPT. 51 , P. 25 - 30 .

Reference (Deposit): NORMAN, L. A. AND STEWART, R. M., 1951 , MINES AND MINERAL RESOURCES OF INYO COUNTY; CALIF. JOUR. MINES AND GEOLOGY, VOL. 51 , NO. 1 ; DIV. OF MINES, P. 59 - 68 .

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.