Last Chance Placer

Past Producer in Costilla county in Colorado, United States with commodities Gold, Tellurium
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. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Controls for ore emplacement
  13. Economic information about the deposit and operations
  14. Mining district
  15. Land status
  16. Ownership information
  17. Links to other databases
  18. Bibliographic references
  19. Reporter information

Geologic information

Identification information

Deposit ID 10011672
MRDS ID D006752
Record type Site
Current site name Last Chance Placer
Alternate or previous names Last Chance No. 3

Geographic coordinates

Geographic coordinates: -105.27445, 37.61613 (WGS84)
Elevation 2944
Relative position 4 MILES N 9 E FROM RUSSELL

Site location context

Political divisions (FIPS codes)

Costilla(county)

Colorado(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Russell(quadrangle 1:24,000 scale)

Blanca Peak(quadrangle 1:100,000 scale)

Trinidad(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Alamosa-Trinchera(hydrologic unit)

Rio Grande Headwaters(hydrologic accounting unit)

Rio Grande Headwaters(hydrologic subregion)

Rio Grande(hydrologic region)

Geographic areas

Country State County
United States Colorado Costilla

Public Land Survey System information

Meridian Township Range Section Fraction State
6th Principal 028S 071W 13 E2 Colorado

Comments on the location information

  • ALTHOUGH DISTRICT ACTUALLY IS IN UNSURVEYED PRIVATE LAND GRANT, SECTIONS REPORTED ARE BASED ON PATTON AND OTHERS' (1910) MAP RATHER THAN PROJECTIONS FROM ADJACENT QUADS. LAT-LONG AND ELEVATIONS DETERMINED FROM TOPO QUAD. SITE OR CLAIM LIES ALONG GRAYBACK GULCH AT AND BELOW JUNCTION WITH BUCKSKIN GULCH. LAT-LONG GIVEN IS CONFLUENCE OF STREAMS ; INFO FROM LAND.ST :(1975)

Commodities

Commodity Importance
Gold Primary
Tellurium Critical Tertiary

Materials information

Materials Type of material
Calaverite Ore
Gold Ore

Analytical data

Result 3 TO 5 COLORS/PAN IN UPPER 6 FT
Result 21 TO 36 COLORS/PAN IN 18-IN. CLAY ZONE ABOVE BEDROCK

Mineral occurrence model information

Model code 56
USGS model code 17a
Deposit model name Placer Au

Host and associated rocks

  • Host or associated Host
    Rock type Unconsolidated Deposit > Sand and Gravel
    Rock unit name Recent Alluvium
    Rock description Terrace Gravel;Recent Alluvium
    Stratigraphic age (youngest) Holocene

Nearby scientific data

(1) -105.27445, 37.61613

Economic information

Geologic structures

Type of structure Regional
Structure description Sierra Blanca Massif, Ft. Garland Embayment

Controls for ore emplacement

  • Valley-Fill And Terrace Gravels Along Major Streams

Comments on the geologic information

  • AU DERIVED FROM LOW-GRADE ORES ON GRAYBACK MTN. FOUND ONLY ALONG PLACER CR. AND TRIBUTARIES HEADING ON OR NEAR GRAYBACK MTN.

Economic information about the deposit and operations

Operation type Surface
Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant No
Year of last production 1936

Mining district

District name Grayback (Russell) District

Land status

Ownership category Private

Ownership information

  • Type Operator
    Owner Casey, William V.
    First year 1910
  • Type Owner
    Owner Trinchera (Estate)
    First year 1910

Reference information

Bibliographic references

Reporter information

Type Date Name Affiliation Comment
Reporter 01-APR-1981 Schwochow, Stephen D. Colorado Geological Survey
Updater 01-MAY-1983 Schwochow, Stephen D. Colorado Geological Survey

Beyond USGS

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

Authoritative Colorado resources

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