Black Rock Group

Producer in Greenlee county in Arizona, United States with commodity Manganese
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. Alteration
  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 10109875
MRDS ID M800416
Record type Site
Current site name Black Rock Group
Alternate or previous names Black Magic Prospects
Related records 10234833

Geographic coordinates

Geographic coordinates: -109.29343, 33.0776 (WGS84)
Elevation 1122
Location accuracy 100(meters)
Relative position 2.2 MILES NORTH OF CLIFTON., Used Arizona Department Of Mineral Resources File Data, Black Rock Mine

Site location context

Political divisions (FIPS codes)

Greenlee(county)

Arizona(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Clifton(quadrangle 1:24,000 scale)

Clifton(quadrangle 1:100,000 scale)

Clifton(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

San Francisco(hydrologic unit)

Upper Gila(hydrologic accounting unit)

Upper Gila(hydrologic subregion)

Lower Colorado(hydrologic region)

Federal lands

Bureau of Land Management(Bureau of Land Management AZ)

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

BLM(Federal land areas administered by BLM)

Geographic areas

Country State County
United States Arizona Greenlee

Public Land Survey System information

Meridian Township Range Section Fraction State
Gila and Salt River 004S 030E 19,20 NE OF NE (19); SE OF SE (20) Arizona

Comments on the location information

  • 1/4 MILE NORTH OF LIMESTONE GULCH IN AN UNNAMED WASH; WASH IS LOCATED 1/4 MILE NE OF MOUTH OF LIMESTONE GULCH. ; INFO FROM LAND.ST :(1973)

Commodities

Commodity Importance
Manganese Critical Primary

Materials information

Materials Type of material
Psilomelane Ore
Pyrolusite Ore

Alteration

  • (Local) Manganese Ore Occurs As Replacement Of Limestone Bordering Large Fault; Replacement Of Crushed Chert Particles In Brecciated Areas

Analytical data

Result 1952 ASSAY VALUES RANGED FROM 12-48% MN.

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Granite
    Rock unit name Precambrian Granite-Granodiorite Complex
    Rock description Precambrian Granite-Granodiorite Complex
    Stratigraphic age (youngest) Late Ordovician
    Stratigraphic age (youngest) Late Ordovician
    Stratigraphic age (youngest) Neoproterozoic
    Stratigraphic age (youngest) Neoproterozoic
  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Rock unit name Longfellow Limestone
    Rock description Longfellow Limestone
  • Host or associated Host
    Rock type Sedimentary Rock > Chemical Sediment > Chert

Nearby scientific data

(1) -109.29343, 33.0776

Economic information

Geologic structures

Type of structure Regional
Structure description Ne Trending Large Fault Between Limestone And Precambrian Granite That Comprises Massivebluffs Overlooking The San Francisco River
Type of structure Local
Structure description Upper Contact Of Chert And Limestone Is Very Irregular; Most Ore Exposures Are Located On The Canyon Walls 20 To 40 Ft Above The Bed Of The Gulch

Ore body information

  • General form IRREGULAR
    Strike NE
    Dip 45 NW
    Thickness 15.24M
    Length 45.72M
    Width 22.86M
    Depth to top 10.67M
  • General form IRREGULAR
    Dip 45 NW

Controls for ore emplacement

  • Manganese Occurs Within Relatively Thick Bed Of Chert In The Longfellow Limestone; Ore Bodies Border Large Fault Between Contact Of Chert And Limestone

Comments on the geologic information

  • WHERE FRACTURING WAS MODERATE, MANGANESE MINERALS WERE DEPOSITED IN THE FRACTURES AND REPLACED PART OF THE LIMESTONE WALLS. IN BRECCIATED AREAS, THE MANGANESE MINERALS REPLACED THE CRUSHED CHERT PARTICLES AND FORMED HIGH-GRADE POCKETS. MANGANESE ORE IS PRIMARILY LOCATED IN THE CHERT BED RATHER THAN IN THE LIMESTONE WALL ROCK OR GRANITE BEDS.

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1906
Discoverer Del M Potter (Owned Property From 1906 To 1949)
Year of first production 1951

Mining district

District name Copper Mountain District

Land status

Ownership category BLM Administrative Area

Ownership information

  • Type Owner
    Owner Matt And Ed Danenhauer; N. T. Jackson; Ernest W Foote : Danenhauer Business Service
    First year 1956

Workings at the site

  • Type of workings Surface/Underground
    Area 0.277HA
    Length 12.19M
    Overall depth 15.24M
    Overall length 51.21M
    Overall width 57.3M

Comments on the workings information

  • DEVELOPMENTS INCLUDED 40 FT ADIT, 50 FT DEEP VERTICAL SHAFT, 27 FT DEEP SHAFT WITH 13 FT OF DRIFTS, 4 OPEN CUTS, SEVERAL SMALL OPEN PROSPECT PITS, AND SMALL MILL ON THE SAN FRANCISCO RIVER. MINING CONSISTED OF OPENING UP SMALL VEINS OR ORE LENSES ON THE SIDES OF THE CANYON WALLS AND SCRAPING OUT ORE.

Comments on development

  • OPERATORS INCLUDED GORDON S. BUTTORFF; TOM U. WOLFE; MANGANESE VALLEY MINES INC; MINES CONTRACTING INC; DANENHAVER BROTHERS; UNITED STATES MANGANESE CORPORATION (BROCK AND SCHUSTER)

Reference information

Bibliographic references

  • Deposit

    USBM IC 7990, P. 101-102.

  • Deposit

    USBM FILES, BLACK ROCK GROUP.

  • Deposit

    ABGMT CLIPPINGS FILE, BLACK ROCK MINE.

  • Deposit

    USGS PP 43, SAN FRANCISCO RIVER GEOLOGY COMMENTS.

  • Deposit

    BENNETT, K.C., 1975, GEOLOGY AND ORIGIN OF THE BRECCIAS IN THE MORENI-METCALF DISTRICT, GREENLEE COUNTY, ARIZONA: M.S. THESIS, UNIVERSITY OF ARIZONA, 153 P.

  • Deposit

    ADMR FILE DATA, BLACK ROCK MINES.

  • Production

    USBM I.C. 7990, P. 101.

General comments

Subject category Comment text
Deposit PROPERTY TOTALS 9 UNPATENTED CLAIMS. STRIKE AND DIP ARE ESTIMATED. AT THE MOUTH OF THE CANYON, THE ERRATICALLY MINERALIZED CHERT BED IS ABOUT 50 FT THICK. 0.1 MILE FURTHER UP THE WASH, ORE-BEARING CHERT BEDS ARE EXPOSED TO LENGTHS OF 150 FT.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-DEC-81 Calder, Susan R. Arizona Bureau of Geology and Mineral Technology

Beyond USGS

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

Authoritative Arizona resources

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