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Unnamed (divide between Christy and Copeland creeks)

Occurrence in Alaska, United States with commodities Chromium, Nickel, Platinum
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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. Nearby scientific data
  10. Economic information about the deposit and operations
  11. Mining district
  12. Links to other databases
  13. Bibliographic references
  14. General comments
  15. Reporter information

Geologic information

Identification information

Deposit ID 10000733
MRDS ID A011372
Record type Site
Current site name Unnamed (divide between Christy and Copeland creeks)

Geographic coordinates

Geographic coordinates: -149.75282, 63.12958 (WGS84)
Relative position This occurrence is at an elevation of about 5,200 feet, about midway between the middle reaches of Christy and Copeland Creeks. the map site is about 1.3 mile north of VABM 5048 (Copeland), in the NE1/4 of sec. 1, T. 21 S., R. 12 W., of the Fairbanks Meridian. The location is accurate to within 0.5 mile. This is location 22 of Cobb (1978: OFR 78-1062), and location E-29 of Balen (1990: OFR 34-90).

Site location context

Political divisions (FIPS codes)

Matanuska-Susitna(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Healy A-6(quadrangle 1:63,360 scale)

Healy S(quadrangle 1:100,000 scale)

Healy(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Chulitna River(hydrologic unit)

Susitna River(hydrologic accounting unit)

South Central Alaska(hydrologic subregion)

Alaska(hydrologic region)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Chromium Critical Primary
Nickel Critical Secondary
Platinum Critical Secondary

Materials information

Materials Type of material
Chromite Ore
Garnierite Ore
Pyrite Ore
Serpentine Gangue

Alteration

  • (Local) Serpentinization of ultramafic intrusive rocks. The serpentinite is altered to quartz-carbonate rock containing disseminated pyrite and stained with garrnierite.

Mineral occurrence model information

Model code 15
USGS model code 8a
Deposit model name Podiform chromite (minor)
Mark3 model number none

Nearby scientific data

(1) -149.75282, 63.12958
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = The country rocks in the area of this occurrence are a tectonically mixed assembleges of Upper Devonian serpentinite, basalt, chert, and gabbro. The occurrence consists of talus blocks of serpentinite(?) containing pods of massive chromite. The blocks occur in an area underlain by serpentinite altered to quartz-carbonate rock containing disseminated pyrite and stained with garnierite. Samples comprising 95% chromite contain 39.5% Cr2O3 and a chromium/iron ratio of 3.1:1, along with traces of platinum group metals (principally rhenium) and 1,000 ppm nickel (Hawley and others, 1969). The platinum values in eight samples were at the lower limit of detection (Balen, 1990: OFR 34-90).
  • Age = Chromite probably was a magmatic segregation in Upper Devonian ultramafic intrusive rocks.

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Valdez Creek

Comments on the workings information

  • Workings / Exploration = There has been surface sampling only. Samples comprising 95% chromite contain 39.5% Cr2O3 and a chromium/iron ratio of 3.1:1, along with traces of platinum group metals (principally rhenium) and 1,000 ppm nickel (Hawley and others, 1969). The platinum values in eight samples were at the lower limit of detection (Balen, 1990: OFR 34-90).

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Hawley and others, 1969

General comments

Subject category Comment text
Deposit Model Name = Podiform chromite (Cox and Singer, 1986; model 8a)

Reporter information

Type Date Name Affiliation Comment
Reporter 07-APR-2000 N. Van Wyck Stevens Exploration Management Corporation

Beyond USGS

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

Maps centered on this site

Authoritative Alaska resources

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