Estrella Mine

The Estrella Mine is a chromium mine located in San Luis Obispo county, California at an elevation of 1,631 feet.

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: Estrella Mine

Commodity

Primary: Chromium
Tertiary: Iridium
Tertiary: Platinum
Tertiary: Palladium
Tertiary: Ruthenium
Tertiary: Rhodium

Location

State: California
County: San Luis Obispo

Land Status

Land ownership: National Forest
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

Type: Underground

Ownership

Not available

Production

Not available

Deposit

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

Physiography

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

Mineral Deposit Model

Model Name: Podiform chromite (minor)

Orebody

Form: NARROW HIGH-GRADE STRINGERS

Structure

Type: L
Description: Numerous Small Joints And Fissures

Alterations

Alteration Type: L
Alteration Text: Dunite And Peridotite Now Mostly Serpentinite

Rocks

Name: Peridotite
Role: Associated
Age Type: Associated Rock
Age Young: Late Jurassic

Name: Peridotite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Late Jurassic

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

Analytical Data

Analytical Data: 1 PGE ANALYSIS: PT=20 PPB
Analytical Data: PD=12 PPB
Analytical Data: RH=1 PPB.
Analytical Data: RU=250 PPB
Analytical Data: IR=93 PPB

Materials

Ore: Chromite
Gangue: Tremolite
Gangue: Opal

Comments

Comment (Production): SAID TO HAVE PRODUCED IN 1918 SOME OF THE RICHEST ORE IN THE COUNTY. 100 LB HIGH-GRADE ORE ON DUMP IN 1941.

Comment (Workings): 2 SHORT ADITS; NORTH ADIT, 30 FT LONG, RUNS N60W

Comment (Location): IN LOS PADRES NATIONAL FOREST. ON SOUTH HALF OF SECTION LINE BETWEEN SEC. 28 AND SEC. 29. LOCATION GIVEN IS MINE SYMBOL SHOWN ON TOPO MAP SOUTHEAST OF CASTRO MINE NEAR SECTION LINE

Comment (Reserve-Resource): NO MINABLE ORE LEFT IN 1941

References

Reference (Deposit): WALKER, G.W., AND GRIGGS, A.B., 1953, GEOLOGICAL INVESTIGATIONS OF CHROMITE IN CALIFORNIA: CALIFORNIA DIVISION OF MINES BULLETIN 134, PT. 2, CH. 2, P. 82.

Reference (Deposit): CARLSON, C.A., AND OTHERS, 1985, ANALYSES FOR PLATINUM-GROUP ELEMENTS IN SAMPLES FROM PODIFORM CHROMITE DEPOSITS, CALIFORNIA AND OREGON: U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 85-442, 14 P.

Reference (Deposit): SMITH, C.T., AND GRIGGS, A.B., 1944, CHROMITE DEPOSITS NEAR SAN LUIS OBISPO, SAN LUIS OBISPO COUNTY, CALIFORNIA: U.S. GEOLOGICAL SURVEY BULLETIN 945-B, P. 36.

Reference (Deposit): ALLEN, J.E., 1941, GEOLOGICAL INVESTIGATION OF THE CHROMITE DEPOSITS OF CALIFORNIA: CALIFORNIA JOURNAL OF MINES AND GEOLOGY V. 37, NO. 1, P. 161.

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.