The La Primera is a chromium mine located in San Luis Obispo county, California at an elevation of 1,775 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
Elevation: 1,775 Feet (541 Meters)
Commodity: Chromium
Lat, Long: 35.3597, -120.68670
Map: View on Google Maps
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.
La Primera MRDS details
Site Name
Primary: La Primera
Secondary: La Primero
Secondary: Hardface
Secondary: El Primero
Commodity
Primary: Chromium
Location
State: California
County: San Luis Obispo
District: Cuesta Pass
Land Status
Land ownership: Federal
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
Type: Minerals Only
Workings
Not available
Ownership
Owner Name: Swartz, Arthur
Percent: 100.0
Home Office: California
Info Year: 1976
Owner Name: Pierce Brothers
Home Office: California
Info Year: 1958
Production
Year: 1952
Description: Lump Ore Mined From 1952-1958 280 Mt @ 44.6 Pct-2.6:1 Cr:Fe
Year: 1952
Description: Concentrates Produced From 1952-1958 11400 Mt @ 45.8 Pct-2.3:1 Cr:Fe
Year: 1952
Description: Ore Mined From 1952-1958 37400 Mt
Year: 1880
Description: Lump Ore Mined 250 Mt
Year: 1918
Description: Lump Ore Mined 25 Mt
Deposit
Record Type: Site
Operation Category: Past Producer
Operation Type: Surface-Underground
Mining Method: Unknown
Year First Production: 1890
Discovery Year: 1890
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
Not available
Orebody
Not available
Structure
Not available
Alterations
Not available
Rocks
Not available
Analytical Data
Not available
Materials
Unknown: Chromite
Unknown: Uvarovite
Unknown: Serpentine
Unknown: Pyroxene
Unknown: Olivine
Comments
Comment (Deposit): 325 TONS WAS SHIPPED PRIOR TO 1918.1952-1958 37,390 LT MILLI MINED,11397 LT.CONCENTRATES PRODUCED. 282 LT.LUMP ORE MINED. ORG RAN 44.6% CR2O3,11.5% FE,CR/FE=2.6.CONCENTRATE RAN 45.8% 13.2 PERCENT CR2O3,CR/FE=2.3. RE-SERVE ESTIMATE-50%=5 FOOT P ION OF EXPOSED ORE,25%=10 FOOT,10%=25 FOOT INADEQUATE RESOURCES FOR COST ANALYSIS. ANALYSIS BY CDMG IN 1976 GAVE FOLLOWING PERCENTAGES-MASSIVE 2 01.57,CR2O3 54.08,FEO 10.37,TOTAL FE 14.15,AL203 14.17,MGO CR/FE 3.36.DISSEMINATE ORE=SI02 14.23,CR2O3 33.62,FEO 09.59 FE 16.72,AL203 13.27,MGO 18.82,CR/FE 1.77.
Comment (Reserve-Resource): MAT 1 COL 1 REPRESENTS AVERAGE ORE GRADE MAT 1 COL 2 REPRESENTS HIGH GRADE ORE MAT 1 COL 3 REPRESENTS LOW GRADE ORE
References
Reference (Deposit): P. 61-63.
Reference (Deposit): CALIF. DIV. MINES BULLETIN 134, 1953, PART II, CHAPT. 2,
Reference (Deposit): CALIF. STATE MINING BUR. BULLETIN 76, 1918, P. 171.
Reference (Deposit): DECEMBER 1993 (P. 6-8).
Reference (Deposit): METAL MINES IN NORTHWEST SAN LUIS OBISPO COUNTY, CA,
Reference (Deposit): COAST REGION. SURFACE WATER DEGRADATION BY INACTIVE
Reference (Deposit): CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD, CENTRAL
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.
