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Trinidad Mine

Past Producer in San Luis Obispo county in California, United States with commodity Chromium
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Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Alteration
  9. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Ore body information
  13. Economic information about the deposit and operations
  14. Land status
  15. Ownership information
  16. Workings at the site
  17. Links to other databases
  18. Bibliographic references
  19. General comments
  20. Reporter information

Geologic information

Identification information

Deposit ID 10104144
MRDS ID M700418
Record type Site
Current site name Trinidad Mine

Geographic coordinates

Geographic coordinates: -120.68625, 35.36303 (WGS84)
Elevation 543
Relative position APPROX. 9 KM N NW OF SAN LUIS OBISPO, CA.

Site location context

Political divisions (FIPS codes)

San Luis Obispo(county)

California(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

San Luis Obispo(quadrangle 1:24,000 scale)

San Luis Obispo(quadrangle 1:100,000 scale)

San Luis Obispo(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Central Coastal(hydrologic unit)

Central California Coastal(hydrologic accounting unit)

Central California Coastal(hydrologic subregion)

California(hydrologic region)

Federal lands

ST(Federal land areas administered by ST)

Geographic areas

Country State County
United States California San Luis Obispo

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 029S;029S;029S 012E;012E;012E 33;33;33 SW; SE; NE California

Comments on the location information

  • LOCATED ON SMALL SPUR HEADING SOUTH OFF MAIN RIDGE OF SANTA LUCIA RANGE. ; INFO FROM LAND.ST :(1975)

Commodities

Commodity Importance
Chromium Critical Primary

Materials information

Materials Type of material
Chromite Ore

Alteration

  • (Local) Serpentinized Dunite

Analytical data

Result MASSIVE ORE AVG. 46% CR2O3, CR TO FE RATIO OF 2.7.

Host and associated rocks

  • Host or associated Host
    Rock type Plutonic Rock > Ultramafic Intrusive Rock > Peridotite > Dunite
    Rock unit name Franciscan;Knoxville
    Rock description Franciscan;Knoxville

Nearby scientific data

(1) -120.68625, 35.36303
ListMap

Economic information

Geologic structures

Type of structure Local
Structure description Volc. And Sed. Rocks Folded Into A Syncline Which Is Roughly Symmetric About Ridge Crest.

Ore body information

  • General form IRREGULAR

Comments on the geologic information

  • THE DEPOSIT OCCURS IN AN ELONGATE NW-SE TRENDING ULTRAMAFIC BODY EXPOSED FOR 16 KM ON THE CREST OF THE MAIN RIDGE OF THE SANTA LUCIA RANGE.

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant No
Year of first production 1885
Year of last production 1958

Land status

Ownership category Military Reservation

Ownership information

  • Type Owner
    Owner Schwartz, A. E. (Mineral Rights)
    Home office C/O K. Pierce, Trinidad Mining Co., Inc., 434 Monterey Ave., Morro Bay, Ca. 93442

Workings at the site

  • Type of workings Surface
    Overall depth 50M
    Overall length 109.73M
    Overall width 100M

Comments on the workings information

  • WORKINGS, 1975, CONSISTED OF A LARGE, BENCHED OPEN PIT.

Reference information

Bibliographic references

  • Deposit

    STINSON, M.C., 1975, CDMG MINERAL PROPERTY REPORT, UNPUBLISHED.

  • Deposit

    SMITH, C.T. AND GRIGGS, A.V., 1944, CHROMITE DEPOSITS NEAR SAN LUIS OBISPO COUNTY, CA., USGS BULL 945-B, PP. 38-40.

  • Deposit

    WALKER, G.W. AND GRIGGS, A.B., 1953, CHROMITE DEPOSITS OF THE SOUTHERN COAST RANGES OF CALIF., CDMG BULL 134 PART 3, CHAPT. 2, PP. 63-64.

General comments

Subject category Comment text
Deposit SEVERAL ORE ZONES WITH AVG. DIMENSIONS OF 30M BY 5M BY 5M WERE RECOVERED.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1982 Oster, Karel L. (Albers, John P.) U.S. Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

External references

Maps centered on this site

Authoritative California resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.