Ear Mountain Deposit

Occurrence in Alaska, United States with commodities Tin, Copper, Uranium, Zinc, Lead, Gold, Silver, Antimony, Tungsten

Geologic information

Identification information

Deposit ID 10094095
MRDS ID A016024
Record type Site
Current site name Ear Mountain Deposit
Alternate or previous names Winfield Shaft, Patented Claims: Surprise, Chloride Fraction, Granite

Geographic coordinates

Geographic coordinates: -166.20902, 65.94291 (WGS84)
Relative position W SIDE OF SUMMIT OF NORTH HILL
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Geographic areas

Country State
United States Alaska

Comments on the location information

  • WINFIELD SHAFT, USBM RI 5493, FIG. 4 AND FIG. 10. LAND STATUS VALUE CALCULATED 6-94 USING GIS OVERLAY ANALYSIS WITH BLM 1:2,500,000 SCALE OWNERSHIP STATUS MAP (1991).

Commodities

Commodity Importance
Tin Primary
Copper Secondary
Uranium Secondary
Zinc Secondary
Lead Secondary
Gold Tertiary
Silver Tertiary
Antimony Tertiary
Tungsten Tertiary

Comments on the commodity information

  • SEE PERTINENT MINERALS FIELD FOR LIST OF MINERALS IDENTIFIED AT EAR MT.

Materials information

Materials Type of material
Cassiterite Ore
Chalcocite Ore
Chalcopyrite Ore
Cinnabar Ore
Galena Ore
Malachite Ore
Scheelite Ore
Sphalerite Ore
Stannite Ore
Stibnite Ore

Alteration

  • (Local) Calc-Silicate Alteration: Early Pyroxene-Plag.-Scapolite Hornfels, Later Stage Fine Grained Skarn With Subequal Pyroxene-Idocrase-Garnet, Cross-Cut By Coarse-Grained Tourmaline-Garnet-Quartz-Sulfide Adjacent To Tourmaline And Fluorite-Bearing Granite.

Analytical data

Result ZONE 1000 FT BY 65 FT ON NE SIDE OF MT. AVERAGES 0.2% SN, TR WO3, 0.28% CU, 0.06% PB, 0.27% ZN, TR AU AND 0.15 OZ/TON AG, USBM RI 5493, TABLE 29, P. 47
Result U-BEARING DIKE CONTAINS UP TO 0.182% EU, AVG. GRADE OF 0.014% EU, USGS BULLETIN 1024-C, P. 89.

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Schist
    Rock unit name Ear Mountain Stock;;;
    Rock description Ear Mountain Stock;;;
  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone

Nearby scientific data

(1) -166.20902, 65.94291

Controls for ore emplacement

  • Granite/Limestone Contact

Comments on the geologic information

  • COUNTRY ROCK CUT BY DIKES AND SILLS OF ALASKITE AND F. GRAINED GRANITE PORPHYRY; AT LEAST ONE MAFIC DIKE; ACCESSORY MONAZITE AND ZIRCON IN GRANITE; ACCESSORY TOPAZ-MUSCOVITE-CASSITERITE IN APOPHYSES; BORDER FACIES TOURMALINIZED, ACCESSORY CHALCOPYRITE. EAR MOUNTAIN STOCK; PORPHYRITIC TO EQUIGRANULAR BIOTITE GRANITE.

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1904

Mining district

District name Port Clarence-Serpentine

Land status

Ownership category State

Comments on the workings information

  • NUMEROUS TRENCHES, SEVERAL SHALLOW SHAFTS AND DRIFTS; WINFIELD SHAFT; 29 FT DEEP WITH DRIFTS ON 29-FT LEVEL AND 35 FT WINZE INCLINED 34 DEGREES.

Comments on development

  • WINFIELD SHAFT SUNK: 1913-1914; USBM TRENCHING: 1953-54.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A016024

Bibliographic references

  • Deposit

    USGS BULLETIN 358, P. 9, 25-32.

  • Deposit

    USGS BULLETIN 733, P. 103-111.

  • Deposit

    USGS BULLETIN 1024-C, P. 65-70, 86-92.

  • Deposit

    USBM RI 5493, P. 2-3, 8, 11, 13, 17, 19, 21, 33-52.

  • Deposit

    USGS CIRCULAR 479, P. 14-15.

  • Deposit

    USGS OFR 77-796-B, P. 7, LOC. 49, 52.

  • Deposit

    GSA ABSTRACTS WITH PROGRAMS, V. 19, NO. 6, P. 374.

  • Deposit

    GSA ABSTRACTS WITH PROGRAMS, V. 19, NO. 6, P. 368.

  • Deposit

    USGS BULLETIN 1786 (IN PRESS), LOC. SP4.

  • Deposit

    GSA BULLETIN, V. 94, NO. 6, P. 769-774.

  • Other Database

    BAG-MF-426-14

General comments

Subject category Comment text
Deposit CASSITERITE, STANNITE, PAIGEITE, CHALCOPYRITE AND OTHER BASE-METAL SULFIDES IN SKARNS AND SPARSE CASSITERITE-QUARTZ VEINS IN LIMESTONE ALONG CONTACT WITH MULTIPHASE BIOTITE GRANITE STOCK; HIGHLY VARIABLE CONTACT METAMORPHIC SILICATE AND SULFIDE ASSEMBLAGE; TOURMALINE-QUARTZ GREISEN VEINS IN UPPER LEVELS OF PLUTON; U OCCURS IN OXIDIZED TOURMALINIZED MAFIC DIKE AND ADJACENT BIOTITE GRANITE; BE-GEOCHEM. ANOMALY SURROUNDS STOCK.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-SEP-1987 Leonard, Kenneth R. (Huber, Donald F.) U.S. Geological Survey
Editor 20-SEP-1994 Mosier, Dan U.S. Geological Survey PARSED OUT HOST ROCK AND ASSOCIATED ROCK TYPES, AGES, UNIT NAMES, AND UNIT AGES.