Cofer Prospect

Occurrence in Louisa county in Virginia, United States with commodities Zinc, Lead, Copper, Gold, Silver, Sulfur-Pyrite, Arsenic
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Ore body information
  13. Controls for ore emplacement
  14. Economic information about the deposit and operations
  15. Mining district
  16. Land status
  17. Ownership information
  18. Workings at the site
  19. Links to other databases
  20. Bibliographic references
  21. General comments
  22. Reporter information

Geologic information

Identification information

Deposit ID 10080205
MRDS ID W031306
Record type Site
Current site name Cofer Prospect

Geographic coordinates

Geographic coordinates: -77.87499, 38.05005 (WGS84)
Elevation 122
Relative position 5.2 KM (3.2 MI) NE OF MINERAL.

Site location context

Political divisions (FIPS codes)

Louisa(county)

Virginia(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Lake Anna West(quadrangle 1:24,000 scale)

Fredericksburg(quadrangle 1:100,000 scale)

Washington(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Pamunkey(hydrologic unit)

Lower Chesapeake(hydrologic accounting unit)

Lower Chesapeake(hydrologic subregion)

Mid Atlantic(hydrologic region)

Geographic areas

Country State County
United States Virginia Louisa

Comments on the location information

  • 0.2 KM (0.1 MI) NW OF STATE ROAD 720, 0.95 KM (0.6 MI) NE OF JUNCTION WITH U.S. HWY 522.

Commodities

Commodity Importance
Zinc Critical Primary
Lead Primary
Copper Primary
Gold Secondary
Silver Secondary
Sulfur-Pyrite Secondary
Arsenic Critical Secondary

Comments on the commodity information

  • TETRAHEDRITE-TENNANTITE IS ARGENTIFEROUS, ELECTRUM IS 50% AU AND 50% AG. ALL MINOR ORE MINERALS OCCUR IN TRACE QUANTITIES

Materials information

Materials Type of material
Bismuth Ore
Bornite Ore
Boulangerite Ore
Chalcocite Ore
Chalcopyrite Ore
Covellite Ore
Digenite Ore
Electrum Ore
Galena Ore
Hematite Ore
Ilmenite Ore
Magnetite Ore
Marcasite Ore
Molybdenite Ore
Pyrite Ore
Pyrrhotite Ore
Rutile Ore
Sphalerite Ore
Biotite Gangue
Feldspar Gangue
Gahnite Gangue
Muscovite Gangue
Quartz Gangue

Alteration

  • (Local) High Temperature, Low To Medium Grade Metamorphism.

Analytical data

Result PYRITE: 30-90%, SPHALERITE: 5-69%, CHALCOPYRITE: LESS THAN 5%, GALENA: LESS THAN 5%, AND ARSENOPYRITE: LESS THAN 3%.

Mineral occurrence model information

Model code 184
USGS model code 28a
Deposit model name Massive sulfide, kuroko
Mark3 model number 93

Host and associated rocks

  • Host or associated Associated
    Rock type Metamorphic Rock > Metavolcanic Rock
    Stratigraphic age (youngest) Early Cambrian
    Stratigraphic age (youngest) Early Cambrian
    Stratigraphic age (youngest) Early Cambrian
    Stratigraphic age (youngest) Early Cambrian
  • Host or associated Associated
    Rock type Metamorphic Rock > Metavolcanic Rock > Felsic Metamorphic Rock
    Rock unit name Chopawamsic Formation
    Rock description Chopawamsic Formation
  • Host or associated Associated
    Rock type Metamorphic Rock > Amphibolite
  • Host or associated Host
    Rock type Metamorphic Rock > Gneiss
    Rock unit name Chopawamsic Formation
    Rock description Chopawamsic Formation
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Siltstone

Nearby scientific data

(1) -77.87499, 38.05005

Economic information

Geologic structures

Type of structure Regional
Structure description Ne-Sw Trend

Ore body information

  • General form POD/LENS (SUBPARALLEL LENSES)
    Thickness 10M

Controls for ore emplacement

  • Elongate Troughs

Comments on the geologic information

  • MINERALOGY SIMILAR TO JAPANESE VOLCANOGENIC DEPOSITS. CORE LOG DELINEATED IN GAIR (1978)

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1955
Discoverer New Jersey Zinc Co.

Mining district

District name Gold-Pyrite Belt

Land status

Ownership category Private

Ownership information

  • Type Owner-Operator
    Owner Piedmont Mineral Associates (Callahan Mining Corp.)

Workings at the site

  • Type of workings Underground
    Length 500M
    Overall depth 110M

Comments on the workings information

  • DRIFTS LOCATED AT 60 AND 110 M LEVELS. IN 1977, SHAFT ENTRANCE WITH LARGE DUMP OF EXCAVATED SULFIDES EVIDENT.

Comments on development

  • DEPOSIT IS ON A STAND-BY STATUS.

Reference information

Bibliographic references

  • Analytical Data

    SRC.REF: MILLER (1978)

  • Deposit

    GAIR, J.E., (ED.), 1978, MASSIVE SULFIDES OF VIRGINIA FIELD TRIP GUIDEBOOK: INTERNATIONAL GEOLOGICAL CORRELATION PROGRAMME, PROJECT NO. 60, 112 P.

  • Deposit

    HODDER, R.W., KAZDA, R.F., AND BOJTOS, P., 1977, AN EXAMPLE OF BASE METAL MASSIVE SULFIDE DEPOSITS FROM WITHIN A TURBIDITE SUCCESSION OF THE VIRGINIA PIEDMONT (ABS.): MINING ENGINEERING, V. 29, NO. 1, P. 83.

  • Deposit

    MILLER, J.W., CRAIG, J.R. AND KAZDA, R.F., 1978, VOLCANOGENIC SULFIDES OF THE MINERAL DISTRICT, LOUISA CO., VIRGINIA (ABS.): GEOLOGICAL SOCIETY OF AMERICA: ABSTRACTS WITH PROGRAMS, V. 10, NO. 7, P. 457

  • Deposit

    MILLER, J.W., CRAIG, J.R. AND KAZDA, R.F., 1979, METAMORPHOSED VOLCANOGENIC ORES OF THE COFER DEPOSIT, MINERAL DISTRICT, LOUISA CO., VIRGINIA (ABS.): GEOLOGICAL SOCIETY OF AMERICA: ABSTRACTS WITH PROGRAMS, V. 11, NO. 4, P. 205-206.

  • Deposit

    MILLER, J.W., JR., 1978, THE ORE MINERALOGY OF THE COFER PROPERTY, LOUISA COUNTY, VIRGINIA: A VOLCANOGENIC MASSIVE SULFIDE DEPOSIT: VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY, UNPUBLISHED MS THESIS.

  • Deposit

    1950 DIREXPL NEW JERSEY ZINC CO.: LOCATED DEPOSIT

  • Deposit

    1975 DIREXPL PIEDMONT MINERAL ASSOCIATES: CONDUCTED EXPLORATORY DRILLING AND MINING TO EVALUATE.

General comments

Subject category Comment text
Deposit Discovery Year: 1950'S
Deposit MAX. THICKNESS ABOVE IS FOR ONE LENS. THERE ARE 4 LENSES.
Deposit PIEDMONT MINERAL ASSOCIATES INCLUDES NEW JERSEY ZINC CO. AND CALLAHAN MINING CORP. ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT

Reporter information

Type Date Name Affiliation Comment
Reporter 01-AUG-1979 Meintzer, Robert E. (Le Van, D.C.) U.S. Geological Survey

Beyond USGS

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