Mount Ripinski

Prospect in Alaska, United States with commodities Gold, Copper, Iron, Palladium, Platinum

Geologic information

Identification information

Deposit ID 10308241
Record type Site
Current site name Mount Ripinski

Geographic coordinates

Geographic coordinates: -135.5161, 59.25575 (WGS84)
Relative position This prospect is on the south side of Mt. Ripinski approximately 0.5 mile south of triangulation station '3563'. It is at an elevation of approximately 1,500 feet near the base of a steep south-facing cliff. Redman and others (1984) show this site as occurrence 1, but they were unable to locate the 100-foot adit reported to occur at this site by Robertson (1956). The location is accurate to within about 0.25 mile.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary
Copper Primary
Iron Primary
Palladium Secondary
Platinum Secondary

Materials information

Materials Type of material
Bornite Ore
Chalcopyrite Ore
Malachite Ore
Pyrite Ore
Pyrrhotite Ore
Calcite Gangue
Quartz Gangue

Mineral occurrence model information

Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Nearby scientific data

(1) -135.5161, 59.25575

Comments on the geologic information

  • Geologic Description = The following description is from Still and others (1991). Chalcopyrite-bornite-bearing quartz-calcite veins and chalcopyrite-bearing metabasalt occur in cliffs and in rubble beneath the cliffs on the south side of Mount Ripinski. Almost all of the quartz veins that were sampled contained low gold values, but some veins contained up to 12.0 ppm gold and 3.97% copper. The metabasalt contained up to 0.60 ppm gold and 3.50 % copper. Eighteen of the 27 samples were analyzed for platinum and palladium. They contained from 0.01 to 0.06 ppm palladium and one sample contained 0.01 ppm platinum. This site is immediately north of the Johnson Creek fault which separates metabasalt to the north from Cretaceous ultramafic rocks, including pyroxenite, to the south. Iron deposits associated with pyroxenite are also reported from this general area but no descriptions are given (Redman and others, 1984). The Cretaceous age of the metabasalts (Still and others, 1991; MacKevett and others, 1974) establishes a maximum age for the mineralization. However, based on fossil evidence from the Chilkat Peninsula to the southeast, Plafker, Hudson and Silberling (1979) and Plafker and Hudson (1980) infer a Late Triassic age for the metabasalts.
  • Age = Cretaceous or younger, or Late Triassic or younger (Plafker, Hudson and Silberling, 1979; Plafker and Hudson, 1980).

Economic information

Economic information about the deposit and operations

Development status Prospect

Comments on exploration

  • Status = Inactive

Mining district

District name Juneau (Skagway subdistrict)

Comments on the reserve resource information

  • Reserves = Robertson (1956) indicates that several billion tons of material with 2 to 10% iron may exist in this area.

Comments on the workings information

  • Workings / Exploration = Redman and others (1984) refer to a report by Robertson (1956) of a 100-foot adit but were unable to find it.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF SK024

Bibliographic references

  • Deposit

    Robertson, E.C., 1956, Magnetite deposits near Klukwan and Haines, southeast Alaska: U.S. Geological Survey Open-File Report 132, 37 p.

  • Deposit

    Plafker George, Hudson, T.L., and Silberling, N.J., 1979, Upper Triassic fossils from a sequence of volcanic and sedimentary rocks on the Chilkat Peninsula, southeastern Alaska, in Johnson, K.M., and Williams, J.R., eds., The United States Geological Survey in Alaska: Accomplishments during 1978: U.S. Geological Survey Circular 804-B, p. B107-B110.

  • Deposit

    Plafker, George, and Hudson, T., 1980, Regional implications of Upper Triassic metavolcanic and metasedimentary rocks on the Chilkat Peninsula, southeastern Alaska: Canadian Journal of Earth Sciences, v. 17, p. 681-689.

  • Deposit

    Berg, H.C., 1984, Regional geologic summary, metallogenesis, and mineral resources of southeastern Alaska: U.S. Geological Survey Open-file Report 84-572, 298 p., 1 plate, scale approx. 1:600,000.

  • Deposit

    Redman, E.C., Retherford, R.M., and Hickok, B.D., 1984, Geology and geochemistry of the Skagway B-2 Quadrangle, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 84-31, 34 p., 4 sheets, scale 1:40,000.

  • Deposit

    Gilbert, W.G., Still, J.C., Burns, L.E., Wier, K.R., and Redman, E.C., 1991, Geochemistry of Haines-Klukwan-Porcupine area, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 91-5, 1 sheet, scale 1:63,360, 75 p.

  • Deposit

    Still, J.C., 1991, Bureau of Mines mineral investigations in the Juneau mining district, Alaska, 1984 - 1988, v. 2, Detailed mine, prospect, and mineral occurrence descriptions, section A, Haines-Klukwan-Porcupine subarea: U.S. Bureau of Mines of Mines Special Publication, 214 p.

  • Deposit

    Still, J.C., Hoekzema, R.B., Bundtzen, T.K., Gilbert, W.G., Wier, K.R., Burns, L.E., and Fechner, S.A., 1991, Economic geology of Haines-Klukwan-Porcupine area, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 91-4, 156 p., 5 sheets, scale 1:63,360.

Comments on the references

  • Primary Reference = Still and others, 1991 (BOM, v. 2, sec. A)

General comments

Subject category Comment text
Deposit Model Name = Possible metamorphic quartz-sulfide veins in association with copper rich metabasalts and an iron-rich ultramafic intrusion (Cox and Singer, 1986; model 36a?).

Reporter information

Type Date Name Affiliation Comment
Reporter 04-FEB-01 T.C. Crafford T. Crafford & Associates