Belmont - Osborne Mine

Past Producer in Calaveras county in California, United States with commodity Gold
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. Host and associated rocks
  9. Nearby scientific data
  10. Ore body information
  11. Economic information about the deposit and operations
  12. Workings at the site
  13. Links to other databases
  14. Bibliographic references
  15. General comments
  16. Reporter information

Geologic information

Identification information

Deposit ID 10102716
MRDS ID M006458
Record type Site
Current site name Belmont - Osborne Mine
Alternate or previous names Knox, Osborne Consolidated Osborne
Related records 10114259

Geographic coordinates

Geographic coordinates: -120.58073, 38.07713 (WGS84)
Elevation 427
Relative position 2 MI W. OF ANGELS CAMP, 1/4 MI NE OF NEGRO HILL

Site location context

Political divisions (FIPS codes)

Calaveras(county)

California(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Angels Camp(quadrangle 1:24,000 scale)

San Andreas(quadrangle 1:100,000 scale)

Sacramento(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Calaveras(hydrologic unit)

San Joaquin(hydrologic accounting unit)

San Joaquin(hydrologic subregion)

California(hydrologic region)

Geographic areas

Country State County
United States California Calaveras

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 003N 013E 30 California

Comments on the location information

  • UTM ACC, SE 1/4 SEC.

Commodities

Commodity Importance
Gold Primary

Comments on the commodity information

  • ORE IN 1930S AVERAGED $10 - $14 PER TON

Materials information

Materials Type of material
Gold Ore
Calcite Gangue
Quartz Gangue

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Slate
  • Host or associated Host
    Rock type Metamorphic Rock > Schist

Economic information

Ore body information

  • Strike N 42 - 55 W
    Dip 72 NE
    Thickness 3.66M

Comments on the geologic information

  • GEOL.DESC: AT LEAST 4 PARALLEL VEINS ARE PRESENT IN A ZONE 75 FT WIDE AND STRIKE FROM N 42 W TO N 55 W. VEINS ARE FROM 4 TO 12 FT WIDE. SOME OF COUNTRY ROCK CONTAINS DISSEMINATED PYRITE. FOOTWALL AMPHIBOLITE SCHIST, HANGING WALL BLACK SLATE AND PHYLLITE. VEINS CONTAIN QUARTZ, CALCITE AND AMPHIBOLITE SCHIST. TWO SYSTEMS OF STRINGERS OF VEIN, ONE PARALLEL SCHISTOSITY THE OTHER ALMOST PERPENDICULAR. MINE ON WESTERN MINERALIZED ZONE OF AMPHIBOLITE SCHIST OF MOTHER LODE

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant No
Production years 1850 - 1880 , 1929 - 1935

Comments on the production information

  • WORKED INTERMITTENTLY 1929 - 1935 , 1850 - 1880 .

Workings at the site

  • Type of workings Surface/Underground
    Area 3.97HA
    Overall depth 106.68M

Comments on the workings information

  • WORKED ON SURFACE TO DEPTH OF 180 FT IN PERIOD TO 1880 MAIN SHAFT IS 350 FT INCLINED SHAFT ON WESTERNMOST VEIN WITH LEVELS AT 70 , 150 , AND 350 FT. OLDER SHAFTS ARE 101 FT ONE TO NORTH AND 164 FT ONE TO SOUTH. SEVERAL CROSSCUTS CONNECT SHAFTS, NUMEROUS DRIFTS AND STOPES

Reference information

Bibliographic references

  • Deposit

    CLARK, W. B., LYDON, P. A, 1962 , MINES AND MINERAL RESOURCES OF CALAVERAS COUNTY, CALIF. COUNTY REPORT 2 ; CALIF. DIV. OF MINES AND GEOLOGY, P 34 - 35 , 65 - 66 , 172 AND PL B

  • Deposit

    LOGAN, C. A., 1934 , THE MOTHER LODE GOLD BELT OF CALIF: CALIF. DIV. OF MINES BULL. 108 P. 146

  • Deposit

    LOGAN, C. A., FRANKE, H., 1936 , MINES AND MINERAL RESOURCES OF CALAVERAS COUNTY; CALIF. JOUR. MINES AND GEOLOGY, VOL. 32 , NO. 3 ; DIV. OF MINES, P 241 - 2 , 315

  • Production

    CLARK ( 1962 )

General comments

Subject category Comment text
Deposit VEINS, AT LEAST 4 PARALLEL VEINS ARE PRESENT IN A 20NE 75 FT WIDE. SOME OF COUNTRY ROCK CONTAIN DISSEMINATED PYRITE. FOOTWALL IS AMPHIBOLITE SCHIST, HANGING WALL BLACK SLATE AND PHYLLITE. VEINS CONTAIN QUARTZ, CALCITE AND AMPHIBOLITE SCHIST. TWO SYSTEMS OF STRINGERS OFF VEIN, ONE PARALLEL TO SCHISTOSITY THE OTHER ALMOST PERPENDICULAR. MINE ON WESTERN MINERALIZED ZONE OF AMPHIBOLITE SCHIST OF MOTHER LODE. VEIN 4 - 12 FT THICK

Reporter information

Type Date Name Affiliation Comment
Reporter 01-FEB-1979 Mateik, R.; 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

Authoritative California resources

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