Boundary

Prospect in Alaska, United States with commodities Barium-Barite, Copper, Arsenic, Cobalt, Zinc
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 10308702
Record type Site
Current site name Boundary
Alternate or previous names Boundary Glacier

Geographic coordinates

Geographic coordinates: -136.47214, 59.34974 (WGS84)
Relative position This prospect is on and immediately to the east of the Alaska-Canada border, 1.75 miles south of Mt. Henry Clay at 5,700 to 6,000 feet in elevation. It is shown as numbers 116 to 121 by Still and others (1984); numbers 247 and 248 of Still and others (1987); and site P by Gilbert and Redman (1989).

Site location context

Political divisions (FIPS codes)

Haines(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Skagway B-4(quadrangle 1:63,360 scale)

Skagway SE(quadrangle 1:100,000 scale)

Skagway C(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Chilkat-Skagway Rivers(hydrologic unit)

Northern Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

BLM(Federal land areas administered by BLM)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Barium-Barite Critical Primary
Copper Primary
Arsenic Critical Secondary
Cobalt Critical Secondary
Zinc Critical Secondary

Materials information

Materials Type of material
Pyrite Ore
Pyrrhotite Ore
Calcite Gangue
Quartz Gangue
Sericite Gangue

Alteration

  • Quartz-sericite (?).

Mineral occurrence model information

Model code 184
USGS model code 28a
Deposit model name Massive sulfide, kuroko
Mark3 model number 93

Nearby scientific data

(1) -136.47214, 59.34974

Economic information

Comments on the geologic information

  • Geologic Description = Still and others (1991) describe this prospect as: 'Narrow bands of iron-stained metasedimentary rocks and altered metabasalt that crop through glacial ice.' 'Float and bedrock samples of sedimentary and volcanic rocks contain up to 0.034 ppm gold, 1.214 ppm silver, 280 ppm zinc, 1,390 ppm copper, 390 ppm cobalt, 400 ppm arsenic, and 200 ppm nickel.' 'A barite rich band hosted in white phyllite contained 47% barium.' Rubicon Minerals (1998) in an unpublished Executive Summary, cites work by Kennecott Alaska Exploration that describes Boundary as: '...quartz-sericite-pyrite schist and felsite with chalcopyrite.' Rubicon also cites Kennecott samples with maximum values of 6.5% copper, 16 ppm lead, 3,610 ppm zinc, 12 ppm silver, and 1.980 ppm gold. Sample descriptions from Still and others (1984) mention phyllite, white phyllite, sericite schist, greenstone and quartzite. These rock types are similar to those at baritic massive sulfide prospects like the Main Zone/Palmer (SK066) and RW Zone (SK067) deposits, and Rubicon Minerals (1998) considers Boundary to be a volcanogenic massive-sulfide system. The phyllitic rocks may reflect a felsic volcanic or altered mafic volcanic protolith. If Boundary is a volcanogenic massive sulfide system correlative with the Windy Craggy deposit in Canada and the Greens Creek deposit on Admiralty Island, then this prospect and others like it in the Mt. Henry Clay area are probably Late Triassic (Still, 1984 [OF 118-84]; Newberry and others, 1997).
  • Age = If Boundary is a volcanogenic massive-sulfide deposit correlative with the Windy Craggy deposit in Canada and the Greens Creek deposit on Admiralty Island, then this prospect and others like it in the Mt. Henry Clay area are probably Late Triassic (Still, 1984 [OF 118-84]; Newberry and others, 1997).

Economic information about the deposit and operations

Development status Prospect
Commodity type Both

Comments on exploration

  • Status = Active

Mining district

District name Juneau (Skagway subdistrict)

Reference information

Bibliographic references

  • Deposit

    Still, J.C., 1984, Stratiform massive sulfide deposits in the Mt. Henry Clay area, southeast Alaska: U.S. Bureau of Mines Open-File Report 118-84, 65 p.

  • Deposit

    Still, J.C., Weir, K.R., Gilbert, W.G., and Redman, E.C., 1984, Stream-sediment, float, and bedrock sampling in the Porcupine mining area, southeast Alaska: U.S. Bureau of Mines Open-File Report 173-84, 19 p.

  • Deposit

    Still, J.C., Gilbert, W.G., and Forbes, R.B., 1987, Final report of stream sediment, float, and bedrock sampling in the Porcupine mining area, southeast Alaska, 1983-1985: U.S. Bureau of Mines Open-File Report 36-87, 35 p., 8 sheets.

  • Deposit

    Gilbert, W.G., and Redman, E.C., 1989, Lode deposits, prospects, and occurrences of the Porcupine mining area, southeast Alaska: U.S. Bureau of Mines Open-File Report 17-89, 1 sheet, scale 1:39,600.

  • 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.

  • Deposit

    Rubicon Minerals, 1998, Palmer VMS Project, southeast Alaska, Executive Summary: unpublished report by Rubicon Minerals Corporation, Vancouver, British Columbia, 25 p.

  • Deposit

    Newberry, R.J., Crafford, T.C., Newkirk, S.R., Young, L.E., Nelson, S.W., and Duke, N.A., 1997, Volcanogenic massive sulfide deposits of Alaska, in Goldfarb, R.J. and Miller, L. D., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, p. 120-150.

Comments on the references

  • Primary Reference = Still and others, 1991

General comments

Subject category Comment text
Deposit Model Name = Besshi- or Kuroko-type massive sulfide (?) (Cox and Singer, 1986; models 28a? or 24b?).

Reporter information

Type Date Name Affiliation Comment
Reporter 04-FEB-2001 T.C. Crafford T. Crafford & Associates

Beyond USGS

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

Authoritative Alaska resources

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