El Fenomeno

Past Producer in Baja California, Mexico with commodities Tungsten, Copper, Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Mineral occurrence model information
  8. Host and associated rocks
  9. Nearby scientific data
  10. Geologic structures
  11. Ore body information
  12. Controls for ore emplacement
  13. Economic information about the deposit and operations
  14. Mining district
  15. Ownership information
  16. Production statistics
  17. Reserves and resources
  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 10104175
MRDS ID MX00229
Record type Site
Current site name El Fenomeno
Alternate or previous names Rosa De Castilla
Related records 10157844

Geographic coordinates

Geographic coordinates: -116.13415, 32.13342 (WGS84)
Elevation 1500
Relative position 10 KM SW OF CORTE DE MADERA.

Site location context

Political divisions (FIPS codes)

Pima(county)

Arizona(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

San Diego(quadrangle 1:250,000 scale)

Geographic areas

Country State
Mexico Baja California

Commodities

Commodity Importance
Tungsten Critical Primary
Copper Tertiary
Gold Tertiary

Comments on the commodity information

  • SCHEELITE AT SURFACE OR IN STRONGLY OXIDIZED FRACTURE ZONES WAS TOO FRIABLE FOR EFFICIENT MILL RECOVERY.

Materials information

Materials Type of material
Scheelite Ore
Axinite Gangue
Calcite Gangue
Chalcopyrite Gangue
Diopside Gangue
Garnet Gangue
Idocrase Gangue
Pyrite Gangue
Pyrrhotite Gangue
Quartz Gangue

Analytical data

Result 0.2 - 0.7% WO3

Mineral occurrence model information

Model code 42
USGS model code 14a
Deposit model name W skarn

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Stratigraphic age (youngest) Pliocene
    Stratigraphic age (youngest) Late Permian
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Marble

Nearby scientific data

(1) -116.13415, 32.13342

Economic information

Geologic structures

Type of structure Local
Structure description Caverns And Wide Fissures In Marble Extend As Far Down As Deepest Workings, 93 M Below Surface.

Ore body information

  • Thickness 17M
    Length 120M
    Width 93M
    Depth to top 0M
    Depth to bottom 93M

Controls for ore emplacement

  • Igneous/Carbonate Contact

Comments on the geologic information

  • QUARTZ DIORITE INTRUDED INTO SERIES OF LATE PALEOZOIC SHALE AND INTERBEDDED LIMESTONE AND IMPURE SANDSTONE, STRONGLY FOLDED AND METAMORPHOSED TO SCHIST, PHYLLITE, HORNFELS, MARBLE AND IMPURE QUARTZITE. TACTITE, MAINLY GARNET AND DIOPSIDE, OCCURS ALONG INTRUSIVE CONTACT BETWEEN QUARTZ DIORITE AND MARBLE, AND IN MANY PLACES FORMS IRREGULAR MASSES WITHIN MARBLE.

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1917
Year of first production 1917

Mining district

District name Los Gavilanes/Ensenada

Ownership information

  • Type Owner-Operator
    Owner Cia. Minera El Fenomeno
    First year 1943

Production statistics

  • Year 1943
    Period 1937-43
    Material ORE W
    Accuracy Estimate
    Description Cp_Grade: ^Ave. 0.7% Wo3
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Ore Tungsten Tungsten 1wt-pct

Comments on the production information

  • CAPACITY OF TWO LARGE PLANTS: 200 TPD. COMMERCIAL ORE WAS MATERIAL CONTAINING AT LEAST 0.4% WO3.

Reserves and resources

  • Type In-situ
    Estimate year 1945
    Commodity Subtype Grade units Group Importance Year
    Tungsten Wo3 0.4 wt-pct Tungsten Major 1945

Workings at the site

  • Type of workings Surface/Underground
    Overall depth 93M

Comments on the workings information

  • 93-M SHAFT WITH 200-FT, 250-FT, AND 300-FT LEVELS. NUMEROUS STOPES ABOVE 200-FT LEVEL.

Comments on development

  • DISC. AND MINED DURING WW1 (PRODUCED 4,000 UNITS TUNGSTATE). REOPENED FOR SEVEN YEARS STARTING IN 1937 (60,000 UNITS PRODUCED).

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit SCHEELITE IN TACTITE; MAINLY GARNET, BUT LOCALLY IDOCRASE, AXINITE, DIOPSIDE, QUARTZ, OR CALCITE PREDOMINATES. SMALL % OF ORE IS IN QUARTZ DIORITE CONTAINING MINOR CALC-SILICATES. MINOR FE-OXIDES AND SECONDARY CU MINERALS IN WEATHERED PORTIONS. SULFIDES (PYRITE, PYRRHOTITE, CHALCOPYRITE AND ARSENOPYRITE OCCUR IN FRESH ROCK. A FEW PEGMATITE DIKES CONTAIN MINOR DISS SCHEELITE ALONG CONTACTS WITH ORE BODIES.MAIN ORE BODY IS FAN-SHAPED TACTITE ZONE AT CONTACT BETWEEN MARBLE AND MAIN DIORITE BODY. LENGTH OF SCHEELITE-BEARING ZONE AT SURFACE: 185 M. LENGTH OF COMMERCIAL ORE BODY (GREATER THAN 0.4% WO3 MATERIAL): 120 M. SIDES OF ORE BODY APPEAR TO CONVERGE TOWARD A POINT IMMEDIATELY BELOW THE BOTTOM OF THE 93-M SHAFT, WHERE ORE BODY IS ONLY 4-5 M LONG AND 3 M WIDE. WIDTH IN UPPER WORKINGS VARIES FROM 0.2 TO 17.0 M (AVE. 4.0 M). BEST ORE WAS IN POCKETS OR LENSES. SOME ORE MINED FROM IRREGULAR VEIN-LIKE MASSES EXTENDING INTO MARBLE. POSSIBLY ANOTHER FAN-LIKE ORE BODY AT N END OF MINE, WHERE
Deposit ORE HAS BEEN STOPED FROM 200-FT LEVEL; ORE ZONE LESS THAN 1.0 M WIDE.
Deposit LARGEST KNOWN W DEPOSIT IN THE SIERRA DE JUAREZ REGION. THE W DEPOSITS IN THE REGION ARE OF THE PYROMETASOMATIC OR REPLACEMENT TYPE, FORMED ADJACENT TO INTRUSIVE QUARTZ DIORITE IN CHEMICALLY FAVORABLE (I.E. CALCAREOUS) BEDS BY REACTION OF MAGMATIC FLUIDS WITH CALCIUM CARBONATE. MOVEMENT OF THE FLUIDS WAS IN PART FRACTURE CONTROLLED. NO COMMERCIAL ORE FORMED WHERE CALCAREOUS BEDS WERE ABSENT. INTRUSION OF THE DIORITE WAS ACCOMPANIED BY METAMORPHISM OF THE SEDIMENTARY TERRANE TO SCHIST, HORNFELS, AND MARBLE. LATE-STAGE PEGMATITE DIKES WERE INJECTED INTO FRACTURES CUTTING BOTH IGNEOUS AND METAMORPHIC ROCKS. THE SIZE AND GRADE OF THE TUNGSTEN DEPOSITS ARE INDEPENDENT OF THE PRESENCE OF PEGMATITES. ; INFO.SRC : 1 PUB

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUL-1987 Staude, John-Mark G. (Page, Norman J.) U.S. Geological Survey
Updater 01-JUN-1988 Leonard, Kenneth R. U.S. Geological Survey

Beyond USGS

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