East Helvetia Deposit

Past Producer in Pima county in Arizona, United States with commodities Copper Sulfide, Molybdenum, Copper Oxide
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. Reserves and resources
  19. Links to other databases
  20. Bibliographic references
  21. General comments
  22. Reporter information

Geologic information

Identification information

Deposit ID 10026900
MRDS ID M000917
Record type Site
Current site name East Helvetia Deposit
Alternate or previous names Rosemont

Geographic coordinates

Geographic coordinates: -110.75985, 31.83319 (WGS84)
Elevation 1999
Relative position 50 KM SOUTHEAST OF TUCSON.

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 25,36 SE4 (25) OF NE4 (36) Arizona

Comments on the location information

  • INFO FROM LAND.ST :1964

Commodities

Commodity Importance
Copper Sulfide Primary
Molybdenum Secondary
Copper Oxide Primary

Materials information

Materials Type of material
Bornite Ore
Chalcocite Ore
Chalcopyrite Ore
Chrysocolla Ore
Cuprite Ore
Malachite Ore
Molybdenite Ore
Pyrite Ore
Biotite Gangue

Alteration

  • (Local) Skarnification, Pyritization, Silicification, Argillization

Analytical data

Result 0.016-0.017% MO

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Quartz Monzonite
    Rock unit name Greaterville Intrusives
    Rock description Greaterville Intrusives
    Stratigraphic age (youngest) Tertiary
    Chronological age 56
  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Quartz Latite
    Stratigraphic age (youngest) Tertiary
    Chronological age 56
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Quartzite
  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Rock unit name Horquilla Limestone;Scherrer Formation, Concha Limestone;Bisbee Group
    Rock description Horquilla Limestone;Scherrer Formation, Concha Limestone;Bisbee Group

Nearby scientific data

(1) -110.75985, 31.83319

Economic information

Geologic structures

Type of structure Local
Structure description Flat Thrust Fault Separating Paleozoic Limestones From Overlying B Isbee Group

Ore body information

  • Depth to top 91.44M

Controls for ore emplacement

  • Intrusions, Lithology, Limestone Skarns

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Medium
Significant No
Discovery year 1961
Year of first production 1875
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 Owner-Operator
    Owner Asarco (American Smelting And Refining Co.)
    First year 1988

Reserves and resources

  • Type In-situ
    Estimate year 1977
    Total resources 162947000mt ore
    Commodity Subtype Grade units Group Importance Year
    Copper Sulfide Cu 0.54 wt-pct Copper Major 1977
    Copper Oxide Cu 0.55 wt-pct Copper Major 1977
  • Type In-situ
    Estimate year 1988
    Total resources 126984000mt ore
    Commodity Subtype Grade units Group Importance Year
    Copper Sulfide CuS 0.62 wt-pct Copper Major 1988
    Molybdenum Mo 0.016 wt-pct Molybdenum Minor 1988
    Copper Oxide CuOx 0.78 wt-pct Copper Major 1988

Comments on development

  • ASARCO INC. ACQUIRED THE PROPERTY AS A 'LONG-TERM COPPER RESERVE" AND HAS NO IMMEDIATE PALNS TO DEVELOP IT.

Reference information

Bibliographic references

  • Deposit

    DREWES, 1971, USGS MAP I-613.

  • Deposit

    JIM KELLY, ANAMAX MINING CO (PERSONAL COMMUN. TO JAN WILT).

  • Deposit

    SAWYER, M.B., GURMENDI, A.C., DALEY, M.R., AND HOWELL, S.B., 1992, PRINCIPAL DEPOSITS OF STRATEGIC AND CRITICAL MINERALS IN ARIZONA: U.S. BUREAU OF MINES SPECIAL PUBLICATION, 334 P.

  • Other Database

    CIMRI

  • Reserve-Resource

    SAWYER AND OTHERS, 1992.

General comments

Subject category Comment text
Deposit OVERLAIN BY 300 FT OF CRET SEDIMENTS ON WEST AND BY 1200 FT ON EAST. PORPHYRY IS NOT VERY MINERALIZED.
Deposit THIS REPORT WAS TAKEN FROM RECORD M000917 OF JAN WILT IN MOLYBDENU M FILE, CONTACT PERSON T.G. THEODORE, USGS ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1983 Peterson, Jocelyn A. U.S. Geological Survey
Updater 01-DEC-1993 Orris, Greta J. U.S. Geological Survey

Beyond USGS

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

Operator history (post-MRDS)

MRDS records operators as of each record's last update (≤ 2019). Some of the operators listed here have since changed hands or dissolved:

Curated by qvyshift.com from publicly-reported M&A activity (SEC filings, press releases, USGS Mineral Yearbooks). Not authoritative — verify against primary sources before relying on it. The MSHA panel above is the current authoritative source for actively-permitted mines.

Authoritative Arizona resources

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