Formoso

Occurrence in Custer county in South Dakota, United States with commodity Mica
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. Geologic structures
  11. Ore body information
  12. Economic information about the deposit and operations
  13. Mining district
  14. Land status
  15. Ownership information
  16. Links to other databases
  17. Bibliographic references
  18. General comments
  19. Reporter information

Geologic information

Identification information

Deposit ID 10010790
MRDS ID D004764
Record type Site
Current site name Formoso

Geographic coordinates

Geographic coordinates: -103.45862, 43.8419 (WGS84)
Elevation 1609
Relative position 2.5 MI SOUTH SOUTHWEST OF MOUNT RUSHMORE NATIONAL MEMORIAL

Site location context

Political divisions (FIPS codes)

Custer(county)

South Dakota(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Iron Mountain(quadrangle 1:24,000 scale)

Mount Rushmore(quadrangle 1:100,000 scale)

Hot Springs(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Middle Cheyenne-Spring(hydrologic unit)

Cheyenne(hydrologic accounting unit)

Cheyenne(hydrologic subregion)

Missouri(hydrologic region)

Federal lands

Black Hills National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Black Elk Wilderness(Wilderness)

Wilderness FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States South Dakota Custer

Public Land Survey System information

Meridian Township Range Section Fraction State
Black Hills 002S 005E 25 South Dakota

Comments on the location information

  • SW 1/4

Commodities

Commodity Importance
Mica Primary

Materials information

Materials Type of material
Mica Ore

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Pegmatite
    Rock unit name Pegmatitic Granite;Pegmatite
    Rock description Pegmatitic Granite;Pegmatite
    Stratigraphic age (youngest) Neoproterozoic
    Stratigraphic age (youngest) Neoproterozoic
  • Host or associated Host
    Rock type Plutonic Rock > Pegmatite

Nearby scientific data

(1) -103.45862, 43.8419

Economic information

Geologic structures

Type of structure Regional
Structure description Cut By Pegmatite Dikes

Ore body information

  • General form NARROW DIKES

Economic information about the deposit and operations

Development status Occurrence
Commodity type Non-metallic
Deposit size Small
Significant No

Mining district

District name Unorganized District

Land status

Ownership category National Forest
Area name Black Hills National Forest

Ownership information

  • Type Owner
    Owner Dunstan, Wilma
  • Type Owner
    Owner Smith, Ethel

Comments on the workings information

  • A FEW PROSPECT PITS

Comments on development

  • LOCATED ON APRIL 26, 1946

Reference information

Bibliographic references

  • Deposit

    U.S. BUREAU OF MINES, 1955, BLACK HILLS MINERAL ATLAS, SOUTH DAKOTA: PART 2, BUREAU OF MINES INFORMATION CIRCULAR 7707

General comments

Subject category Comment text
Deposit MICA-RICH ZONES UP TO 12 INCHES IN WIDTH CARRY RUBY MICA IN BOOKS UP TO 5 INCHES IN DIAMETER

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUL-1980 Barari, Rachel A. U.S. Geological Survey

Beyond USGS

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

External references