Exposed Reef Mines

Producer in Santa Cruz county in Arizona, United States with commodities Copper, Silver, Lead, Zinc, Gold, Iron
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 10048345
MRDS ID M899932
Record type Site
Current site name Exposed Reef Mines
Alternate or previous names Blue Eagle and Exposed Reef Group, Saint Louis Mine
Related records 10283184

Geographic coordinates

Geographic coordinates: -110.74874, 31.49458 (WGS84)
Elevation 1326
Relative position 4 MILES SOUTH OF PATAGONIA, BETWEEN FLUX AND ANDES MINE GROUPS

Site location context

Political divisions (FIPS codes)

Santa Cruz(county)

Arizona(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Harshaw(quadrangle 1:24,000 scale)

Nogales(quadrangle 1:100,000 scale)

Nogales(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Santa Cruz(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 Santa Cruz

Public Land Survey System information

Meridian Township Range Section Fraction State
Gila and Salt River 022S 016E 30 SW OF NE Arizona

Comments on the location information

  • LOCATED ON NE SIDE OF ALUM GULCH; BLUE EAGLE GROUP LOCATED 1/2 MILE TO SW, ON SOUTH SIDE OF ALUM GULCH ; INFO FROM LAND.ST :(1979)

Commodities

Commodity Importance
Copper Primary
Silver Primary
Lead Secondary
Zinc Critical Secondary
Gold Secondary
Iron Tertiary

Comments on the commodity information

  • ORES OF EXPOSED REEF AND BLUE EAGLE GROUPS ARE PRIMARILY ARGENTIFEROUS COPPERS WITH SOME GOLD A ND STRONG IRON CONTENT

Materials information

Materials Type of material
Bornite Ore
Chalcocite Ore
Chalcopyrite Ore
Cuprite Ore
Galena Ore
Pyrite Ore
Sphalerite Ore
Tetrahedrite Ore
Hematite Gangue

Alteration

  • (Local) Extensive Surface Oxidation

Analytical data

Result ASSAY VALUES AVERAGED 15% CU, 15 OZ./TON AG, $2.00/TON AU

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Rock unit name Mt Wrightson Formation;Josephine Canyon Diorite
    Rock description Mt Wrightson Formation;Josephine Canyon Diorite
    Stratigraphic age (youngest) Late Cretaceous
    Stratigraphic age (youngest) Late Cretaceous
  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Intermediate Volcanic Rock > Trachyandesite
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Rhyolite
  • Host or associated Host
    Rock type Plutonic Rock

Nearby scientific data

(1) -110.74874, 31.49458

Economic information

Geologic structures

Type of structure Regional
Structure description General Structure Common To Regional Formations Is A Sheeting Which Dips 40 Nnw
Type of structure Local
Structure description Main Vein Paralleled By Banded Iron Formation-Hematite Dike Showing Some Copper Stain, And By Several Smaller Parallel Quartz Veins; 5 Principal Veins On Property

Ore body information

  • General form IRREGULAR
    Strike W AND NW
    Dip NEARLY VERTICAL
    Length 914.4M
    Width 9.14M
  • General form IRREGULAR
    Dip NEARLY VERTICAL

Controls for ore emplacement

  • Ores Occur Principally In Veins, Fissures, And Contacts In Rhyolite, And Contacts With Grano-Porphyry And Quartz Diorite

Comments on the geologic information

  • CLAIMS LOCATED ON LARGE BELT OF COARSE RHYOLITE PORPHYRY THAT INCLUDES NEARLY ALL OF RED MOUNTAIN; PORPHYRY BELT IS PROFUSELY IMPREGNATED WITH CRYSTALS AND GRAINS OF PYRITE, CHALCOPYRITE, AND CHALCOCITE

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1875

Mining district

District name Harshaw District

Land status

Ownership category National Forest

Ownership information

  • Type Owner
    Owner De Saulles, Albert
    First year 1953
  • Type Owner
    Owner Sibold, Helen And Doris
    First year 1953

Comments on the production information

  • NO RECORDS OF PRODUCTION

Workings at the site

  • Type of workings Underground
    Overall depth 95.1M

Comments on the workings information

  • DEVELOPMENTS INCLUDED 312-FT DEEP EXPOSED REEF SHAFT; 36-FT LONG TUNNEL AND OPEN-CUT ON SAINT LOUIS CLAIM.500 FT EXPOSED REEF TUNNEL THAT CUTS 3 VEINS; NUMBEROUS WINZES AND RAISES EXTENDING FROM SHAFTS AND TUNNELS; 300-FT TUNNEL AND 112-FTSHAFT ON RED FOX NO.1 CLAIM; TOTAL OF 11 TUNNELS, FROM 10-500 FT LONG, ON PROPERTY; 600 FT OF DRIFTS AND CROSSCUTS

Comments on development

  • EXPOSED REEF AND BLUE EAGLE PROPERTIES COMPRISE 22 LODE CLAIMS TOTALLING 440 ACRES AND INCLUDING CLAIMS OF BORDER PATROL, LIME BANK NO.1-5, DONNA MARIA, MILL SITE, REED TUNNEL, IRON BANK, BLUE EAGLE NO. 1-2, ST. LOUIS, NORTH STAR, LOG CABIN, COW BOY POWDER HOUSE, EXPOSED REEF, SILVER TUNN EL LUCKY DAY, SILVER STAR INVINCIBLE, ST. PATRICKS, OLD BOY ROGERS, RE D FOX NO. 1-4; OWNERS INCLUDED JOHN FARLEY D. DOWD, J.B. SHANNON

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit NUMEROUS VEINS ON PROPERTY CONTAINING LOW-GRADE SULFIDE ORES; MAIN VEIN TRENDS NW-SE ACROSS SEVERAL CLAIMS; VEINS GENERALLY HAVE VERY WIDE MINERALIZED OUTCROP COPPER ORE BODIES THAT INCREASE, BOTH IN SIZE AND VALUES, WITH DEPTH; VEINS VARY IN WIDTH FROM 1-30 FT
Deposit Discovery Year: LATE 1800'S
Deposit SEE ALSO: BLUE EAGLE MINE, INVINCIBLE PROSPECT ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1982 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.

External references

Authoritative Arizona resources

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