Mammoth Bar

Producer in Placer county in California, United States with commodities Gold, Platinum, Osmium, Iridium, Palladium, Rhodium
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. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Ore body information
  12. Controls for ore emplacement
  13. Economic information about the deposit and operations
  14. Mining district
  15. Land status
  16. Ownership information
  17. Links to other databases
  18. Bibliographic references
  19. General comments
  20. Reporter information

Geologic information

Identification information

Deposit ID 10109520
MRDS ID M045267
Record type Site
Current site name Mammoth Bar
Alternate or previous names Pacific Gold Dredging

Geographic coordinates

Geographic coordinates: -121.00547, 38.92045 (WGS84)
Elevation 183
Location accuracy 100(meters)
Relative position ON MIDDLE FORK 3 MI EAST OF CONFLUENCE OF AMERICAN RIVER AND MIDDLE FORK, ABOUT 4 MI NORTHEAST OF AUBURN, Accurate On Bar

Site location context

Political divisions (FIPS codes)

Placer(county)

California(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Auburn(quadrangle 1:24,000 scale)

Sacramento(quadrangle 1:100,000 scale)

Sacramento(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

North Fork American(hydrologic unit)

Lower Sacramento(hydrologic accounting unit)

Sacramento(hydrologic subregion)

California(hydrologic region)

Federal lands

Bureau of Land Management(Bureau of Land Management CA)

Bureau of Land Management CA BLM(Type of land area)

BLM(Federal land areas administered by BLM)

Geographic areas

Country State County
United States California Placer

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 012N 009E 05 NEAR CENTER California

Comments on the location information

  • LOCATION GIVEN IS FOR WEST END OF BAR AT WEST EDGE OF SECTION. TOPO MAP HAS NO UTM COORDINATES

Commodities

Commodity Importance
Gold Primary
Platinum Critical Secondary
Osmium Tertiary
Iridium Critical Tertiary
Palladium Critical Tertiary
Rhodium Critical Tertiary

Materials information

Materials Type of material
Gold Ore

Analytical data

Result PGE SAMPLE ANALYZED: 37.22% PT, 34.72% IR, $28.02 AU, TR PD AND RH (LOGAN, P. 109). AU GRADES ESTIMATED AT 0.0048 OZ/YD (80 PPB)

Mineral occurrence model information

Model code 119
USGS model code 39a
Deposit model name Placer Au-PGE
Mark3 model number 54

Host and associated rocks

  • Host or associated Host
    Rock type Unconsolidated Deposit > Gravel
    Stratigraphic age (youngest) Holocene

Nearby scientific data

(1) -121.00547, 38.92045

Economic information

Ore body information

  • General form STREAM SEDIMENT DEPOSITS
    Depth to top 0M

Controls for ore emplacement

  • Stream Hydraulics

Comments on the geologic information

  • BEDROCK IS SLATE DECOMPOSED TO 1 FT DEPTH

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Deposit size Small
Significant No
Production years 1914-1927

Mining district

District name Upper American River Area

Land status

Ownership category Private

Ownership information

  • Type Operator
    Owner El Dorado And Placer Counties Gold Mining And Power Co., Pacific Gold Dredging Co.
    First year 1910

Comments on the production information

  • IN EARLY YEARS OF DREDGING, PGE WERE NOT SAVED. GRAVELS PROBABLY AVERAGED GREATER THAN $0.10/YD AND BEDROCK GREATER THAN $1/YD

Comments on the workings information

  • DREDGING. DREDGERS NEAR MAMMOTH BAR.

Reference information

Bibliographic references

  • Deposit

    LOGAN, C.A., 1927, PLACER COUNTY: CALIFORNIA STATE MINING BUREAU, 23RD REPORT OF THE STATE MINERALOGIST, NO. 3, P. 284.

  • Deposit

    LOGAN, C.A., 1919, PLATINUM AND ALLIED METALS IN CALIFORNIA: CALIFORNIA STATE MINING BUREAU BULLETIN 85, P. 29-30, 109.

  • Deposit

    WARING, C.A., 1919, PLACER COUNTY: CALIFORNIA STATE MINING BUREAU, 15TH REPORT OF THE STATE MINERALOGIST, PT. 3, P. 386.

General comments

Subject category Comment text
Deposit PACIFIC GOLD DREDGING CO. ALSO OPERATED ON THE NORTH FORK AMERICAN RIVER (SEE M045269) ; INFO.SRC : 1 PUB LIT
Deposit DREDGING WAS CARRIED OUT ON BARS OF OLD HYDRAULIC TAILINGS. GRAVELS AVERAGED 28 FT DEEP
Deposit SEE ALSO: MRDS M045269.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-NOV-74 Blair, Will N. U.S. Geological Survey
Updater 01-JAN-89 Peterson, Jocelyn A. U.S. Geological Survey

Beyond USGS

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

Authoritative California resources

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