Broad Top Mine

Past Producer in Pima county in Arizona, United States with commodities Silver, Copper, Gold, Tungsten, Molybdenum
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. Production statistics
  19. Links to other databases
  20. Bibliographic references
  21. General comments
  22. Reporter information

Geologic information

Identification information

Deposit ID 10039628
MRDS ID M050524
Record type Site
Current site name Broad Top Mine
Alternate or previous names Alta Copper
Related records 10113504

Geographic coordinates

Geographic coordinates: -110.75818, 31.85152 (WGS84)
Elevation 1768
Relative position 2 MI ESE OF HELVETIA.

Site location context

Political divisions (FIPS codes)

Pima(county)

Arizona(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Helvetia(quadrangle 1:24,000 scale)

Fort Huachuca(quadrangle 1:100,000 scale)

Nogales(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Rillito(hydrologic unit)

Santa Cruz(hydrologic accounting unit)

Middle Gila(hydrologic subregion)

Lower Colorado(hydrologic region)

Federal lands

Coronado 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 Arizona Pima

Public Land Survey System information

Meridian Township Range Section Fraction State
Gila and Salt River 018S 015E 24 SE4 Arizona

Commodities

Commodity Importance
Silver Primary
Copper Primary
Gold Secondary
Tungsten Critical Secondary
Molybdenum Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Gold Ore
Malachite Ore
Molybdenite Ore
Pyrite Ore
Scheelite Ore
Silver Ore

Alteration

  • (Local) Oxidized, Silication Of Limestone

Host and associated rocks

  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Quartz Latite
    Stratigraphic age (youngest) Late Permian
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Quartzite

Nearby scientific data

(1) -110.75818, 31.85152

Economic information

Geologic structures

Type of structure Local
Structure description Strongly Brecciated Fault Zone

Ore body information

  • General form IRREGULAR
    Strike EW
    Dip 80 S

Controls for ore emplacement

  • Fault Zone Near Contact Of Sediments And Porphyry

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant No
Year of first production 1956
Year of last production 1959

Mining district

District name Helvetia-Rosemont District

Land status

Ownership category National Forest
Area name Coronado National Forest

Ownership information

  • Type Operator
    Owner Lewisohn Copper Co.

Production statistics

  • Year 1959
    Period 1955-1959
    Material ORE
    Accuracy Estimate
    Description Cp_Grade: ^5% Cu, 10 Oz/T Ag, Minor Au
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Ore Silver Silver 282g/mt
    Trace Ore Copper Copper 5wt-pct

Comments on the workings information

  • OPEN PIT AND TUNNELS FROM ADJOINING EXILE CLAIM.

Reference information

Bibliographic references

  • Deposit

    KEITH, 1974, ABM BULL 189, P. 124.

  • Deposit

    CORNWALL, H.R., 1973, FIELD EXAM (?).

  • Other Database

    CIMRI

  • Production

    KEITH, 1974.

General comments

Subject category Comment text
Deposit THIS REPORT REPRESENTS A MERGER OF ORIGINAL RECORD M050524 WITH RECORD D000790 OF JAN WILT IN MOLYBDENUM FILE, CONTACT PERSON T.G. THEODORE, USGS. ; INFO.SRC : 1 PUB LIT; 3 FIELD OBSERV
Deposit DISSEMINATED SCHEELITE AND SPOTS OF MOLYBDENITE IN FAULT ZONE.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1983 Peterson, Jocelyn A. U.S. Geological Survey
Updater 01-JAN-1975 Wilt, Jan And Elliot, J.E. Alabama Geological Survey

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.