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Great Expectation Mine

Occurrence in Santa Clara county in California, United States with commodity Manganese
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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. Nearby scientific data
  9. Ore body information
  10. Economic information about the deposit and operations
  11. Links to other databases
  12. Bibliographic references
  13. Reporter information

Geologic information

Identification information

Deposit ID 10033591
MRDS ID M020192
Record type Site
Current site name Great Expectation Mine
Related records 10189470

Geographic coordinates

Geographic coordinates: -121.48574, 37.36353 (WGS84)
Relative position ON ONE OF THE HEADWATERS OF COLORADO CREEK

Site location context

Political divisions (FIPS codes)

Santa Clara(county)

California(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Mount Stakes(quadrangle 1:24,000 scale)

San Jose(quadrangle 1:100,000 scale)

San Jose(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

San Francisco Bay(hydrologic unit)

San Francisco Bay(hydrologic accounting unit)

San Francisco Bay(hydrologic subregion)

California(hydrologic region)

Geographic areas

Country State County
United States California Santa Clara

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 005S 004E 36 California

Comments on the location information

  • UTM APPROX

Commodities

Commodity Importance
Manganese Critical Tertiary

Materials information

Materials Type of material
Rhodochrosite Ore

Analytical data

Result ORE GRADE 35 TO 40 PERCENT MANGANESE, 15 PERCENT SILICA.

Nearby scientific data

(1) -121.48574, 37.36353
ListMap

Economic information

Ore body information

  • Thickness 3.05M

Comments on the geologic information

  • GEOL.DESC: ORE BODY IS MASSIVE LENS LYING WITHIN BEDDED RADIOLARIAN CHERTS AND SHALES, PARALLEL TO THEIR BEDDING. GENERAL STRIKE IS N 70 W, DIPPING 45 S. CHERT IS WHITE OR PINK AND THIN-BEDDED TO MASSIVE. ORE IS UNDERLAIN BY THIN-BEDDED GREEN SHALES AND CHERTS, WITH SHARP CONTACTS. ORE IS MOSTLY MANGANESE OXIDE WITH RESIDUAL SILICA PATCHES. CARBONATE IS FOUND INSIDE BLOCKS AS A GRAY ORE, PINK RHODOCHROSITE, AND A BROWN CARBONATE (SIDERITE?). THE 2 DEFINITE ORE HORIZONS ARE 100 FT. APART STRATIGRAPHICALLY.

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Significant No

Reference information

Bibliographic references

  • Deposit

    D.O.M. BULL. 152 1950 PP. 250 - 251

  • Deposit

    D.O.M. BULL. 125 1943 P. 177

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JAN-1978 Killman, K.; Albers, J. U.S. Geological Survey

Beyond USGS

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

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.