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North Fork Mine

Past Producer in Sierra county in California, United States with commodities Gold, Lead
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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. 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 10086519
MRDS ID X025403
Record type Site
Current site name North Fork Mine

Geographic coordinates

Geographic coordinates: -120.85409, 39.49766 (WGS84)
Elevation 1494
Relative position 1/2 MI N OF FOREST

Site location context

Political divisions (FIPS codes)

Sierra(county)

California(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Alleghany(quadrangle 1:24,000 scale)

Truckee(quadrangle 1:100,000 scale)

Chico(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Yuba(hydrologic unit)

Lower Sacramento(hydrologic accounting unit)

Sacramento(hydrologic subregion)

California(hydrologic region)

Federal lands

Tahoe National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States California Sierra

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 019N 010E 21 California

Comments on the location information

  • UTM ACC. SE 1/4

Commodities

Commodity Importance
Gold Primary
Lead Tertiary

Comments on the commodity information

  • HIGH GRADE ORE SHOOTS 75 TO 100 FT ALONG DRIFT, ASSOC W ARSENOPYRITE

Materials information

Materials Type of material
Galena Ore
Gold Ore
Pyrite Ore
Quartz Gangue
Talc Gangue

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Gabbro
    Stratigraphic age (youngest) Late Permian
  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Intermediate Volcanic Rock > Andesite
  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Granite
  • Host or associated Host
    Rock type Plutonic Rock > Mafic Intrusive Rock > Gabbro
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Slate
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Marble
  • Host or associated Host
    Rock type Metamorphic Rock > Metavolcanic Rock > Mafic Metamorphic Rock > Greenstone
  • Host or associated Host
    Rock type Metamorphic Rock > Schist
  • Host or associated Host
    Rock type Metamorphic Rock > Serpentinite
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Intermediate Volcanic Rock > Andesite
  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Granite

Nearby scientific data

(1) -120.85409, 39.49766
ListMap

Economic information

Ore body information

  • Strike NNW
    Dip W
    Thickness 3.05M

Comments on the geologic information

  • FEW IN-10 FT THICK QTZ VEIN, W SMALL STRINGERS CONTAINING ABUNDANT ALBITE. LATER QTZ VEINS CROSS EARLIER, W ASSOCIATED PYRITE & CARBONATE. FROZEN INTO HANGING WALL OF CRUSHED SLATE. FOOTWALL WELL DEFINED W GOUGE MAYBE ANDESITIC TUFF OR SLATE. PROBABLY 2 BRANCHES W PARALLEL STRIKE. MOVEMENT ALONG VEIN SHOWN ALSO BY GREENSTONE OR TUFF BEING IN HANGING WALL & BLACK CONGLOMERATIC SLATE IN FOOTWALL, & INDICATING REVERSE FAULTING. VEIN EXPLORED ON 3 LEVELS FOR 450 FT. SML GABBRO DIKE FAULTED ON E TO W ROCK CHIEFLY BLACK CONGL. SL, OVERLAIN BY ALTERED TUFF. OTHER SML DIKES OF GABBRO, OR ALTERED MORE BASIC RX. SML APLITE DIKE. VEINS APPROX. ALINE W DIADEM VEIN. ABUNDANT EVIDENCE OF POST MINERAL OPENING OF FISSURES. ON 2ND LEVEL NR WHERE XCUT REACHES VEIN, SPLITTING OF VEIN IS PRONOUNCED, & FOOTWALL CONTAINS SMALL DIKES OF FLAKY TALCOSE SCHIST, POSSIBLY DERIVED FROM SERP. STEEP E DIPPING SHEAR ZONE 200 FT E OF VEIN ON LOWEST LEVEL, MAY CORRELATE W SML QTZ STRINGERS ON 1ST LEVEL, 180 FT ABOVE.
  • SHAFT IN ANDESITE BRECCIA, 13 DEGREE SLOPE REACHES BEDROCK AT 230 FT E DIPPING VEIN MAY ALIGN W AMETHYST. S FORK, RED STAR MINES

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant No

Comments on the production information

  • VEIN DISCOVERED IN OLD PLACER WORKINGS. ON MAY 31 , 1875 , $5000 TAKEN OUT IN 8 HRS.

Workings at the site

  • Type of workings Surface/Underground
    Overall depth 76.2M

Comments on the workings information

  • INCLINED & VERT SHAFT, LEVELS AT 55 , 145 , 235 FT, 1000 FT OF DRIFTS, XCUTS,

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit VEIN, ORE SHOOT

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1979 Hayden, F. (Albers, J.) 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.