Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for Educators
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsUsersBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Dishna River Prospect, Iditarod District, Yukon-Koyukuk Borough, Alaska, USA

This page is currently not sponsored. Click here to sponsor this page.
 
 
Locality equivalent to #74 of Miller, Bundtzen, and Gray (2005), Table 1.
Location: This prospect is on a knob along a ridge overlooking the headwaters of the Dishna River. It is about 0.5 mile southwest of hill 1528, about 0.8 mile northeast of hill 1803, and about 0.5 mile west-southwest of the center of section 22, T. 29 N., R. 44 W., of the Seward Meridian. The location is accurate.
Geology: This prospect consists of brecciated, pod-shaped, quartz-sulfide veins that cut sheared shale and sandstone of the Upper Cretaceous. Kuskokwim Group (Miller and Bundtzen, 1994; Bundtzen and Miller, 1997; Miller, Bundtzen, and Gray, 2005). The rocks are sericitized and alunite has been reported (Don Harris, oral communication, 1983). Numerous slickensides in the wall rock suggests that the prospect occurs along a major, high-angle, fault. Individual brecciated veins strike N05E to N05W and dip steeply to vertically. Mineralization consists of sulfide-bearing masses in quartz that locally contain up to 25 percent stibnite and 3-5 percent arsenopyrite (Bundtzen and Miller, 1997). At least three individual veins have been recognized over a total width of about 20 feet. Caved and overgrown prospect pits were dug before World War II. The area has long been regarded as having economic potential and the prospect is a plausible source for placer gold and cinnabar found in the Dishna River (Don Harris, oral communication, 1983). Eighteen chip-channel samples were taken at uniform intervals along the largest vein for about 460 feet. The samples average 2.46 parts per million (ppm) gold, 5,200 ppm antimony, and 4,500 ppm arsenic (Bundtzen and Miller, 1997; Miller, Bundtzen, and Gray, 2005). The highest grade sample contained 11.0 ppm gold, more than 1.00 percent antimony, more than 1.00 percent arsenic, more than 10.0 ppm mercury, and 1.0 ppm silver. Based on the surface sampling, Bundtzen and Miller (1997) estimated a resource of abut 41,000 tons of material that averages 2.46 ppm gold and 0.52 percent antimony.
Workings: Caved and overgrown prospect pits were dug before World War II. The area was mapped and sampled by the U.S. Geological Survey and the Alaska Division of Geological and Geophysical Surveys in 1986.
Alteration: The host rocks are sericitized and alunite has been reported.
Production: Not determined; possibly small production from old pits.
Reserves: Based on the surface sampling, Bundtzen and Miller (1997) estimated a resource of about 41,000 tons of material that averages 2.46 ppm gold and 0.52 percent antimony.

Commodities (Major) - Au, Sb; (Minor) - Ag, As, Hg
Development Status: Undetermined.
Deposit Model: Simple Antimony deposit (Cox and Singer, 1986; model 27d).

Mineral List



4 entries listed. 4 valid minerals.

The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

McGimsey, R.G., Miller, M.L., and Arbogast, B.F., 1988, Paper version of analytical results, and sample locality map for rock samples from the Iditarod quadrangle, Alaska: U.S. Geological Survey Open-File Report 88-421-A, 110 p., 1 sheet, scale 1:250,000. Miller, M.L., and Bundtzen, T.K., 1994, Generalized geologic map of the Iditarod quadrangle, Alaska showing potassium-argon, major oxide, trace element, fossil, paleocurrent, and archeological sample localities: U.S. Geological Survey Miscellaneous Field Studies Map MF-2219-A, 48 pages; 1 sheet, scale 1:250,000. Miller, M.L., Bundtzen, T.K., and Gray, J.E., 2005, Mineral resource assessment of the Iditarod quadrangle, west-central Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-2219-B, scale 1:250,000, pamphlet.

Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2018, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: April 24, 2018 15:23:50 Page generated: January 15, 2015 11:09:38
Go to top of page