Nail Allocthon

Occurrence in Alaska, United States with commodities Chromium, Nickel

Geologic information

Identification information

Deposit ID 10001707
MRDS ID A012490
Record type Site
Current site name Nail Allocthon
Alternate or previous names Nickel Creek, Rick's Nickel Prospect, Noribu Claims
Related records 10160794

Geographic coordinates

Geographic coordinates: -144.87424, 64.75611 (WGS84)
Relative position 88.5 KM N 25 E OF DELAT JUNCTION, AK
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Geographic areas

Country State
United States Alaska

Comments on the location information

  • COINCIDENT WITH VABM "NAIL"; MINERALIZATION OCCURS IN ULTRAMAFIC BODY OVER 60 SQ KM IN AREA LAND STATUS VALUE CALCULATED 6-94 USING GIS OVERLAY ANALYSIS WITH BLM 1:2,500,000 SCALE OWNERSHIP STATUS MAP (1991).

Commodities

Commodity Importance
Chromium Primary
Nickel Tertiary

Comments on the commodity information

  • NO ANOMALOUS NI FOUND IN 1984 USBM STUDY, THOUGH AREA WAS STAKED FOR NI

Materials information

Materials Type of material
Chromite Ore
Magnetite Gangue

Alteration

  • (Local) Silica-Carbonate Replacement Of Serpentinized Peridotite At Base Of Thrust Sheet

Host and associated rocks

  • Host or associated Associated
    Rock type Metamorphic Rock > Schist > Greenschist
    Rock unit name Nail Allocthon
    Rock description Nail Allocthon
  • Host or associated Host
    Rock type Plutonic Rock > Ultramafic Intrusive Rock > Peridotite > Dunite
    Rock unit name Nail Allocthon
    Rock description Nail Allocthon

Nearby scientific data

(1) -144.87424, 64.75611

Comments on the geologic information

  • THE TABULAR ULTRAMAFIC BODY AT NAIL RIDGE COMPRISES A THRUST SHEET OVERLYING A COMPLEX ASSEMBLAGE OF GREENSCHIST FACIES METAMORPHIC ROCKS; UNALTERED PORTION OF ULTRAMAFIC BODY IS COMPOSED DOMINANTLY OF HARZBURGITE, WITH 10-15% DUNITE, AND MINOR GABBRO; ALTERATION AT BASE CONSISTS OF SERPENTINIZED PERIDOTITE UNDERLAIN BY ORANGE-WEATHERING QUARTZ-OPAL-CHALCEDONY-ANKERITE-FUCHSITE ROCK WITH SERPENTINE VEINLETS, WHICH IS IN TURN UNDERLAIN BY MASSIVE GRAY SILICA-MAGNESITE-DOLOMITE ROCK. "NAIL" ALLOCTHON; USBM OFR 176-84.

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Deposit size Small
Significant No

Mining district

District name Fairbanks

Comments on the reserve resource information

  • USBM INVESTIGATION CONCLUDED THAT (1) THE ULTRAMAFIC ROCKS DO NOT CONSTITUTE A POTENTIAL CHROMITE RESOURCE, (2) NO SIGNIFICANT AU OR PT-GROUP ELEMENTS ARE PRESENT, (3) ANOMALOUS CU, SB, AS AND AG FOUND IN ONE OCCURRENCE OF ALTERED ROCK IS TOO LIMITED IN EXTENT AND MADE OF OCCURRENCE DOES NOT SUGGEST THE LIKELIHOOD OF ECONOMIC CONCENTRATIONS OF THESE ELEMENTS BEING PRESENT, AND (4) EXTENSIVE ZONE OF MAGNESITE-RICH SILICA ROCK HAS LOW ECONOMIC POTENTIAL DUE TO INACCESSIBILITY AND THE EXISTENCE OF CHEAPER ALTERNATIVE SOURCES OF MAGNESITE IN THE U.S.

Comments on development

  • 3 LODE CLAIMS STAKED FOR NI IN 1953; SEE DEPOSIT DESCRIPTION COMMENTS; USBM BENEFICIATION AND METALLURGICAL TESTS, 1984, SHOWED ORE TO BE SUBECONOMIC

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A012490

Bibliographic references

  • Deposit

    USGS OFR 78-529D, P. 32, LOC. 26

  • Deposit

    USGS BULL 1246, P. 221

  • Deposit

    TDM PAM 1, P. 16, 18

  • Deposit

    USBM OFR 176-84

  • Other Database

    BAG-OFR-78-529D-26

General comments

Subject category Comment text
Deposit TABULAR ULTRAMAFIC BODY 12 KM LONG AND 610 M THICK CONTAINS 0.25 TO 4.0% COARSE DISSEMINATED CHROMITE OVER WIDE AREA; CHROMITE ALSO OCCURS IN RARE PODS MEASURING ABOUT 1 FT BY 3 FT; OVERALL CHROMITE CONTENT OF BODY IS LESS THAN 1%; ALTHOUGH PORTIONS OF NAIL RIDGE WERE AT ONE TIME STAKED FOR NI, ONLY TRACE AMOUNTS WERE FOUND IN SILICA-CARBONATE ZONE ADJACENT TO SERPENTINIZED PERIDOTITE DURING 1984 USBM INVESTIGATION
Deposit PROSPECTORS FOR NI MAY HAVE MISTAKEN FUCHSITE IN ALTERED ROCK FOR GARNIERITE; NI CONTENT OF THE BODY IS VERY LOW ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT
Deposit THIS SITE NAME WAS CREATED BY THE REPORTER OR OTHER USGS EMPLOYEE BASED ON PROXIMITY TO SOME MAJOR GEOGRAPHIC FEATURE.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUL-1986 Leonard, Kenneth R. (Elliott, R. L.) U.S. Geological Survey
Editor 02-SEP-1994 Mosier, Dan U.S. Geological Survey PARSED OUT HOST ROCK AND ASSOCIATED ROCK TYPES, AGES, UNIT NAMES, AND UNIT AGES.