Red Top

Past Producer in Alaska, United States with commodity Mercury

Geologic information

Identification information

Deposit ID 10002312
MRDS ID A013220
Record type Site
Current site name Red Top

Geographic coordinates

Geographic coordinates: -158.53266, 59.27932 (WGS84)
Relative position The Red Top mercury mine is located on the top of the southern peak of Marsh Mountain. It is at an elevation of about 1,150 feet and 3.1 miles east of the village of Aleknagik. This mine is locality 3 of Cobb (1972 [MF 375]; 1976 [OF 76-606]).
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Mercury Primary

Materials information

Materials Type of material
Cinnabar Ore
Calcite Gangue
Dickite Gangue
Dolomite Gangue
Hematite Gangue
Limonite Gangue
Quartz Gangue

Alteration

  • (Local) Hematite and limonite, closely associated with cinnabar and dickite, line the walls of some veins.

Mineral occurrence model information

Model code 176
USGS model code 27
Deposit model name Disseminated epithermal mercury antomony

Host and associated rocks

  • Host or associated Host
    Stratigraphic age (youngest) Jurassic

Nearby scientific data

(1) -158.53266, 59.27932

Comments on the geologic information

  • Geologic Description = Placer cinnabar was discovered in 1941 in Arcana Creek, which drains eastward from the center of Marsh Mountain; follow-up exploration the next year discovered the lode deposits of the Red Top mine (Sainsbury and MacKevett, 1965, p. 57). The U. S. Defense Minerals Exploration Administration funded 10,000 feet of surface dozer trenching in 1952 and the driving of an upper adit and drifts totaling 560 feet of underground workings in 1955. Subsequently, a lower adit and drifts totaling about 920 feet of underground workings were driven by mining companies. Exploration drilling was completed from the lower adit workings in 1958. C. L. Sainsbury mapped the surface and underground workings in 1959 (Sainsbury and MacKevett, 1965, p. 57). Surface trenching exposed ore from which 22 flasks of mercury were recovered, and a total of 60 flasks of mercury were recovered by 1959. In 1959, the amount of stockpiled ore was estimated to contain at least another 60 flasks of recoverable mercury (Sainsbury and MacKevett, 1965, p. 58). Although Pennington (1959) reported that exploration had found ore that contained an estimated 1,400 flasks of mercury, production for the Red Top mine probably totals about 100 flasks of mercury.? the host rocks for the Red Top cinnabar deposits are interbedded, very fine- to very coarse-grained graywacke, calcareous graywacke, and siltstone. These rocks are probably correlative with Jurassic clastic sedimentary rocks like those in the southeast part of the Hagemeister Island quadrangle (Jk unit of Hoare and Coonrad, 1978; Decker and others, 1994, figure 1). Individual beds vary from a few inches to several feet or more in thickness. The beds generally strike east to northeast and in the area of the mine are folded broadly into a south-plunging syncline.? the principal controls on cinnabar mineralization are faults that fracture and brecciate massive graywacke. Faults in siltstone tend to be gouge-filled and tight; they commonly are not hosts for cinnabar deposits. The principal fault in the Red Top mine strikes west to northwest and dips 45 to 80 degrees south. This arcuate reverse fault has had consistent right-lateral oblique slip, including some displacements that postdate mineralization. It has been traced over a distance of about 1,250 feet at the surface and over 400 feet in the subsurface. Smaller subparallel faults and splays, generally striking west-northwest and dipping 40 to 50 degrees south, have also been mapped in the subsurface, particularly in the hanging wall of the main fault (Sainsbury and MacKevett, 1965, plate 7).? Cinnabar, the only sulfide mineral identified in the Red Top mine, occurs in discrete small veins up to 4 inches wide that have been traced laterally up to 200 feet but are commonly a few tens of feet long. Cinnabar also occurs as disseminations in fractured graywacke and in the carbonate gangue that cements graywacke breccia; as replacements of graywacke fragments and
  • Geologic Description = dolomite in breccia; and as breccia fragments in or along massive carbonate pods. Dolomite or ankeritic dolomite and later calcite are the most common gangue minerals. The carbonate minerals occur as discontinuous pods and lenses along the faults and as cement in breccia. Other gangue minerals include hematite, limonite, scarce quartz, and fairly common dickite (Sainsbury and MacKevett, 1965, p. 61). The grade of mineralization is highly variable. Production has been from selected high-grade material. A sample of muck from a lower adit drift assayed 0.59 percent Hg, and a large grab sample from the lower adit dump assayed 1.09 percent Hg (Sainsbury and MacKevett, 1965, p. 64). Two cinnabar-rich samples from the Red Top mine contained less than 10 ppb Au and 150 and 7,000 ppm Sb (Hawley and others, 1969).? Surface sampling of soils and nearby stream sediments suggests that the area surrounding the Red Top mine on Marsh Mountain may contain other occurrences of mercury mineralization (Eakin, 1968). Cinnabar reported from Wood River gravels (Malone, 1962, p. 57) could have been derived from the area of the Red Top mine.
  • Age = Late Cretaceous or Tertiary. The Red Top deposit postdates regional deformation of the host Jurassic sedimentary rocks and is probably similar in age to other mercury deposits of southwest Alaska that postdate regional deformation of Cretaceous sedimentary rocks.
  • Age = Host rock is Jurassic.

Economic information

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic

Comments on exploration

  • Status = Probably inactive

Mining district

District name Bristol Bay region

Comments on the production information

  • Production Notes = Surface trenching exposed ore from which 22 flasks of mercury were recovered and a total of 60 flasks of mercury were recovered by 1959. In 1959, the amount of stockpiled ore was estimated to contain at least another 60 flasks of recoverable mercury (Sainsbury and MacKevett, 1965, p. 58). Although Pennington (1959) reported that exploration had found ore that contained an estimated 1,400 flasks of mercury, production for the Red Top mine probably totals about 100 flasks of mercury.

Comments on the workings information

  • Workings / Exploration = Placer cinnabar was discovered in 1941in Arcana Creek, which drains eastward from the center of Marsh Mountain; follow-up exploration the next year discovered the lode deposits of the Red Top mine (Sainsbury and MacKevett, 1965, p. 57). The U. S. Defense Minerals Exploration Administration funded 10,000 feet of surface dozer trenching in 1952 and the driving of a upper adit and drifts totaling 560 feet of underground workings in 1955. Subsequently, a lower adit and drifts totaling about 920 feet of underground workings was driven by mining companies. Exploration drilling was completed from the lower adit workings in 1958. C. L. Sainsbury mapped the surface and underground workings in 1959 (Sainsbury and MacKevett, 1965, p. 57).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A013220
USGS Alaska Resource Data File ARDF DI002

Bibliographic references

  • Deposit

    Pennington, J.W., 1959, Mercury. A materials survey, with a chapter on resources by Edgar H. Bailey: U.S. Bureau of Mines Information Circular 7941, 92 p.

  • Deposit

    Malone, Kevin, 1962, Mercury occurrences in Alaska: U.S. Bureau of Mines Circular 8131, 57 p.

  • Deposit

    Sainsbury, C.L. and MacKevett, E.M., Jr., 1965, Quicksilver deposits of southwestern Alaska: U.S. Geological Survey Bulletin 1187, 89 p.

  • Deposit

    Eakins, G.R., 1968, A geochemical investigation of the Wood River-Tikchik area, southwestern Alaska: Alaska Division of Mines and Minerals, Geochemical Report 17, 31 p.

  • Deposit

    Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Dillingham, Sleetmute, and Taylor Mountain quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-606, 92 p.

  • Deposit

    Hoare, J.M., and Coonrad, W.L., 1978, Geologic map of the Goodnews and Hagemeister Island quadrangles region, southwestern Alaska: U.S. Geological Survey Open-File Report 78-9-B, two sheets, scale 1:250,000.

  • Deposit

    Decker, J., Bergman, S.C., Blodgett, R.B., Box, S.E., Bundtzen, T.K., Clough, J.G., Coonrad, W.L., Gilbert, W.G., Miller, M.L., Murphy, J.M., Robinson, M.S., and Wallace, W.K., 1994, Geology of southwestern Alaska, in Plafker, G. and Berg, H.C., eds., The Geology of Alaska: Boulder, Colorado, Geological Society of America, The Geology of North America, v. G-1, p. 285-310.

  • Deposit

    Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Dillingham, Sleetmute, and Taylor Mountains quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-606, 92 p.

  • Deposit

    Hawley, C.C., Martinez, E.E., and Marinenko, John, 1969, Geochemical data on the South ore zone, White Mountain mine, and on the gold content of other mercury ores, southwestern Alaska, in Some shorter mineral resources investigations in Alaska: U.S. Geological Survey Circular 615, p. 16-20.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Dillingham quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-375, 1 sheet, scale 1:250,000.

Comments on the references

  • Primary Reference = Sainsbury and MacKevett, 1965

General comments

Subject category Comment text
Deposit Model Name = Cinnabar vein and breccia deposits (Cox and Singer, 1986; model 27?)

Reporter information

Type Date Name Affiliation Comment
Reporter 15-MAR-01 Travis L. Hudson Applied Geology