Tres Hermanos Mine

Producer in Guanacaste, Costa Rica with commodities Gold, Silver
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. Ore body information
  11. Economic information about the deposit and operations
  12. Mining district
  13. Ownership information
  14. Reserves and resources
  15. Links to other databases
  16. Bibliographic references
  17. Reporter information

Geologic information

Identification information

Deposit ID 10007895
MRDS ID CS00129
Record type Site
Current site name Tres Hermanos Mine
Alternate or previous names Includes the Tres Hermanos, El Limon, Terciopela, Balsa, Nispero, Pedernal, and Palo Negro Veins.

Geographic coordinates

Geographic coordinates: -84.94022, 10.30801 (WGS84)

Site location context

Political divisions (FIPS codes)

Guanacaste(province)

Costa Rica(country)

North America(continent)

Land(continent)

Geographic areas

Country State
Costa Rica Guanacaste

Commodities

Commodity Importance
Gold Primary
Silver Secondary

Materials information

Materials Type of material
Electrum Ore
Galena Ore
Gold Ore
Sphalerite Ore
Stibnite Ore
Hematite Gangue
Pyrite Gangue
Quartz Gangue

Mineral occurrence model information

Model code 151
USGS model code 25d
Deposit model name Epithermal vein, Sado
Mark3 model number 28

Host and associated rocks

  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Dacite
    Stratigraphic age (youngest) Pliocene
    Stratigraphic age (youngest) Pliocene
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Dacite

Nearby scientific data

(1) -84.94022, 10.30801

Economic information

Ore body information

  • General form VEIN
    Thickness 7.92M
    Length 2011.68M

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Significant No

Mining district

District name Abangares District

Ownership information

  • Type Owner
    Owner Cia. Minera Guanacaste, S. A.; Ariel Resources ).
    First year 1990

Comments on the production information

  • ORE SECOND QUARTER 1994 PRODUCTION FROM TRES HERMANOS. AU (1994) FIRST 6 MONTHS; AU (1993) LAST 6 MONTHS IN MATOPALO MILL WHICH ALSO PRODUCES FROM SAN MARTIN. WHICH PROCESSED 20778 TONS GRADING 0.145 OZ/TON AU.

Reserves and resources

  • Type In-situ
    Estimate year 1995
    Total resources 2940600000mt ore
    Commodity Subtype Grade units Group Importance Year
    Gold Au 9.42 g/mt Gold Major 1995

Comments on the workings information

  • SEVERAL ADITS.

Comments on development

  • ORE PROCESSED IN THE MATAPALO MILL.

Reference information

Bibliographic references

  • Deposit

    REITZ, M. F., 1902, THE GOLD MINES OF COSTA RICA: ENG. MIN. J., V. 74, NO. 7, P. 213.

  • Deposit

    GIOVANI SOSTO, MINE OWNER, ORAL COMMUNICATION, 1986.

  • Deposit

    ORGANIZACION DE LOS ESTADOS AMERICANOS, 1978, DIAGNOSTICO DEL SECTOR MINERO: SAN JOSE, ORGANIZACION DE LOS ESTADOS AMERICANOS, 91 P.

  • Deposit

    VISITED BY USGS SCIENTISTS, 1986.

  • Deposit

    ANON., 1994, ARIEL'S SAN MARTIN MINE PROCEEDING ON SCHEDULE: LATIN AMERICAN MINING NEWS, JUNE 8, 1994, P. 52.

  • Deposit

    ANON., 1995, ARIEL LARGEST PRODUCER OF GOLD IN COSTA RICA: THE NORTHERN MINER, MARCH 27, 1995, V. 81, NO. 4, P. B-1 AND B-2.

  • Production

    ANON. (1994)

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1986 Howe, Stephen S. (Cox, Dennis P.) U.S. Geological Survey
Updater 01-SEP-1994 Page, Norman J. U.S. Geological Survey
Updater 01-APR-1995 Page, Norman J. U.S. Geological Survey

Beyond USGS

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