Viloco Mine

Producer in La Paz, Bolivia with commodities Tin, Tungsten, Arsenic, Zinc, Copper, Molybdenum
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  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. Ownership information
  16. Reserves and resources
  17. Workings at the site
  18. Links to other databases
  19. Bibliographic references
  20. General comments
  21. Reporter information

Geologic information

Identification information

Deposit ID 10021648
MRDS ID DE00333
Record type Site
Current site name Viloco Mine
Alternate or previous names Araca

Geographic coordinates

Geographic coordinates: -67.63561, -16.87268 (WGS84)
Elevation 4775
Relative position AT VILOCO

Site location context

Political divisions (FIPS codes)

La Paz(province)

Bolivia(country)

South America(continent)

Land(continent)

Geographic areas

Country State
Bolivia La Paz
Bolivia La Paz

Comments on the location information

  • APPROXIMAT LOCATION

Commodities

Commodity Importance
Tin Critical Primary
Tungsten Critical Secondary
Arsenic Critical Tertiary
Zinc Critical Tertiary
Copper Tertiary
Molybdenum Tertiary

Materials information

Materials Type of material
Cassiterite Ore
Chalcopyrite Ore
Molybdenite Ore
Scheelite Ore
Sphalerite Ore
Wolframite Ore
Chlorite Gangue
Pyrite Gangue
Pyrrhotite Gangue
Quartz Gangue
Tourmaline Gangue

Alteration

  • (Local) Contact Metamorphism (Hornfels, Tourmaline), Silicification, Sericitization

Mineral occurrence model information

Model code 77
USGS model code 20b
Deposit model name Sn-polymetallic vein

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Granite
    Rock unit name Quimsa Cruz (Tres Cruces) Batholith
    Rock description Quimsa Cruz (Tres Cruces) Batholith
    Stratigraphic age (youngest) Miocene
    Stratigraphic age (youngest) Miocene
    Stratigraphic age (youngest) Late Silurian
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Shale
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Sandstone
    Rock unit name Quimsa Cruz (Tres Cruces) Batholith
    Rock description Quimsa Cruz (Tres Cruces) Batholith

Nearby scientific data

(1) -67.63561, -16.87268

Economic information

Geologic structures

Type of structure Regional
Structure description On Both Flanks Of N10-20w Viloco Syncline On Western Fringe Of The Loligo-Emio Tres Cruces Batholith

Ore body information

  • Strike N 60 E
    Dip VERTICAL

Controls for ore emplacement

  • Best Ore Found In Vein Intersections Within Metamorphosed Sandstone. When Veins Pass Into Hornfelsed Shale, They Branch And Become Sterile.

Comments on the geologic information

  • CONTACT METAMORPHISM EXTENDS 600 M AWAY FROM GRANITE/SANDSTONE-SHALE CONTACT.

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Significant No
Discovery year 1902
Year of last production 1985

Ownership information

  • Type Operator
    Owner Empresa Minera De Araca . Empresa Minera Viloco (Comibol Subsidiary . Upper Levels
    First year 1926
    Last year 1952
  • Type Owner
    Owner Empresa Minera De Araca ; Corporacion Minera De Bolivia (Comibol)
    First year 1926
    Last year 1952

Comments on the production information

  • ANNUAL: W CONTENT OF TUNGSTEN ORE PRODUCTION. ANNUAL PRODUCTION REPORTED AS AN AVERAGE FOR 1980-84. FROM 1939-44 THE MINE PRODUCED 600 T OF WO3. IT WAS OPERATED BY EMPRESA ESTANIFERA DE ARACA.

Reserves and resources

  • Type In-situ
    Estimate year 1990
    Total resources 90930000mt ore
    Commodity Subtype Grade units Group Importance Year
    Tin Sn 1.67 wt-pct Tin Major 1990

Comments on the reserve resource information

  • (2) THREE YEARS PRODUCTION

Workings at the site

  • Type of workings Underground
    Overall depth 625M

Comments on the workings information

  • SHAFLTS, CROSSCUTS, DRIFTS. CUT AND FILL MINING.

Comments on development

  • ACQUIRED BY GRUPO PATINO IN 1926 AND OPERATED AS EMPRESA MINERA DE ARACA. NATIONALIZED IN 1952, BUT NEARLY DEPLETED. NEW VEIN DISCOVERED IN 1961. THE PRINCIPAL AND GINEBRA VEINS ARE NOTED FOR THEIR LARGE CASSITERITE CRYSTALS OF MUSEUM QUALITY. ; ECON.COM: GRAVITY CONCENTRATION OF CASSITERITE; FLOATATION RECOVERY OF SULFIDES.

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit VEINS UP TO 1.5 M WIDE. LATERAL ZONING WITH MOLYBDENITE-WOLFRAMITE-SCHEELITE IN THE CONTACT ZONE, PASSING OUTWARD INTO CASSITERITE-SCHEELITE-BASE METAL ZONE. SN MINERALIZATION EXTENDS FROM 500 TO 2000 M OUTWARD FROM THE CONTACT ZONE. ORE SHOOTS AT VEIN INTERSECTIONS WITHIN SANDSTONE PITCH 35-50 SW. THE MAIN ORE SHOOT WAS 500 M LONG AND 55O M DEEP. VEINS ARE OXIDIZED (CASSITERITE ONLY) TO ABOUT 400 M DEPTH. SN CONTENT DIMINISHES GRADUALLY WITH DEPTH IN THE SULFIDE ZONE. ABOUT 80% OF PRODUCTION CAME FROM MAIN ORE SHOOT. A TOTAL OF 14 VEINS, MOSTLY NARROW, WERE PRODUCTIVE.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-SEP-1985 Pasitschniak, Anna Geological Survey of Canada
Updater 01-DEC-1993 Long, Keith R. U.S. Geological Survey

Beyond USGS

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