Laskawonda

Prospect in Alaska, United States with commodities Silver, Gold, Copper

Geologic information

Identification information

Deposit ID 10001576
MRDS ID A012328
Record type Site
Current site name Laskawonda
Alternate or previous names Schoenbar, Forest Avenue quarry, Prison parking lot, Nevada lode, American Legion quarry, Cape Fox

Geographic coordinates

Geographic coordinates: -131.64177, 55.34974 (WGS84)
Relative position This site includes several prospects or occurrences in about a square-mile area in and near the city of Ketchikan. They are at elevations ranging from near sea level to about 300 feet, and from 0.1 to 0.7 mile northwest of Ketchikan Creek (sections 19, 24, and 30, T. 75 S., R. 91 E., of the Copper River Meridian). The location is accurate within about 0.5 mile. The site represents loc. 65 in Elliott and others (1978), and locs. 276-280 in Maas and others (1995). Old workings on several of the prospects are concealed by housing and other city development, or are on private lots and have been filled in or covered by the owners (Maas and others, 1995, p. 194).
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Gold Primary
Copper Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
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

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Schist

Nearby scientific data

(1) -131.64177, 55.34974

Comments on the geologic information

  • Geologic Description = This part of Revillagigedo Island is underlain mainly by marine, andesitic or basaltic volcanic rocks and pelitic sedimentary rocks that are intruded by Cretaceous stocks, sills, and dikes of feldspar-porphyritic granodiorite, and by a stock and probably related plugs of Tertiary gabbro (Berg and others, 1988). The strata were regionally metamorphosed to greenschist-grade phyllite and semischist in Late Cretaceous time. They subsequently were contact metamorphosed to hornblende hornfels: locally, near some of the Cretaceous granodiorite contacts, and, more widely, peripheral to the Tertiary gabbro. The premetamorphic age range of the strata is uncertain. Berg and others (1988) note that they closely resemble Upper Jurassic to mid-Cretaceous flysch and volcanic rocks nearby on Gravina Island. The country rocks are cut by a high-angle fault along Tongass Narrows that displays about 4 miles of right-lateral offset.? the Laskawonda (also referred to as Schoenbar in early reports) prospect consists of a N50W, 50NE sulfide-bearing band of phyllite and greenschist, cut by sulfide-bearing quartz fissure veinlets. The sulfide minerals are pyrite and chalcopyrite, and there were early reports of gold and silver (Wright and Wright, 1908, p. 152; Cobb and Elliott, 1980, p. 69). The deposit was explored in the early 1900s by two shafts, one of which was 85 feet deep, a short tunnel, and surface stripping.? The following five occurrences were examined in the early 1990s by Maas and others (1995, locs. 276-280), who named them either from U.S. Bureau of Mines claim records, or, informally, for local landmarks.? Loc. 276 (Maas and others, p. 201): Forest Avenue quarry. Samples of silicified(?) volcanic rocks contained up to 222 ppb Au, 2970 ppm Cu, and 111 ppm Mo.? Loc. 277: Prison parking lot. A 2-foot sample of silicified(?) volcanic rock contained 2.1 ppm Au.? Loc. 278: Nevada lode. A 7-foot sample of silicified(?) greenstone contained 1282 ppb Au and 5705 ppm Cu. A shaft on this property was plugged.? Loc. 279: American Legion quarry. Samples of unidentified material contained up to 2235 ppm Zn.? Loc. 280: Cape Fox. Samples of unidentified material contained up to 20 ppb Au. This property was explored in the early 1900s by a 24-foot adit and a shaft, which have been plugged.
  • Age = The quartz fissure veins that crosscut the metamorphic foliation probably are Late Cretaceous or younger.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Ketchikan

Comments on the workings information

  • Workings / Exploration = Workings in the early 1900s included surface cuts and several short adits, shafts, and tunnels most of which have been covered by housing or commercial development, or filled in.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A012328
USGS Alaska Resource Data File ARDF KC068

Bibliographic references

  • Deposit

    Wright, F.E., and Wright, C.W., 1908, The Ketchikan and Wrangell mining districts, Alaska: U.S. Geological Survey Bulletin 347, 210 p.

  • Deposit

    Elliott, R.L., Berg, H.C., and Karl, Susan, 1978, map and table describing metalliferous and selected nonmetalliferous mineral deposits, Ketchikan and Prince Rupert quadrangles, Alaska: U.S. Geological Survey Open-file Report, 78-73-B,17 p., scale 1:250,000.

  • Deposit

    Cobb, E.H., and Elliott, R.L., 1980, Summaries of data on and lists of references to metallic and selected nonmetallic mineral deposits in the Ketchikan and Prince Rupert quadrangles, Alaska: U.S. Geological Survey Open-File Report 80-1053, 154 p.

  • Deposit

    Berg, H.C., Elliott, R.L., and Koch, R.D., 1988, Geologic map of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Mineral Investigations Series Map MF-1807,27 p., scale 1:250,000.

  • Deposit

    Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.

Comments on the references

  • Primary Reference = Wright and Wright, 1908; Maas and others, 1995

General comments

Subject category Comment text
Deposit Model Name = Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)

Reporter information

Type Date Name Affiliation Comment
Reporter 02-JUL-1999 H.C. Berg U.S. Geological Survey