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 EducatorsMindat ArticlesThe ElementsBooks & Magazines
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
Mining CompaniesStatisticsUsersMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryMineral Photography

Thetis Prospects, Chichagof District, Sitka Borough, Alaska, USA

This page is currently not sponsored. Click here to sponsor this page.
 
 
Location: There may be several old workings in the vicinity and the location used here is an adit that was found by Bittenbender and others (1999) The Thetis prospect is at an elevation of about 850 feet, about 0.7 mile north-northeast of Mount Verstovia in the NW1/4SW1/4 sec. 28, T. 55 S., R. 64 E. The prospect is location P-115 of Bittenbender and others (1999), location 55 of Cobb (1972, 1978), and MAS no. 0021140016 (U.S. Bureau of Land Management, 2002). The location is probably accurate but Cobb (1972, 1978) places it about a mile to the northeast based on a 1898 map by Becker that is probably more diagrammatic than precise.
Geology: The Thesis prospect was located in 1888 (DeArmond 1997). By 1898, the prospect had been developed by two adits, a sawmill, and 2 prospecting mills (Becker, 1898). He described the deposit as a reticulated quartz vein 2 1/2 feet thick with calcite, pyrrhotite, and galena. A mill test of the ore indicated that it contained about $7 in gold (about 0.35 ounce of gold per ton) and $1 in silver. Becker described the host rock as schistose diorite. But modern mapping by Loney and others (1975) assign the rocks to the Jurassic and Triassic, Khaz Formation which consists of graywacke, greenschist, metachert, phyllite, and minor limestone--all cataclastically deformed. Bittenbender and others (1999) located and sampled a 30-foot adit here that cut a quartz vein less than a foot thick, and several thin quartz veinlets The gold values in 4 samples were below the detection limit.
Workings: In 1898, the workings consists of two adits, a sawmill, and two prospecting mills. One 30-foot adit was located by Bittenbender and others (1999).
Age: Triassic or younger based on the age of the host rock.
Production: Apparently none.

Commodities (Major) - Au, Pb
Development Status: None
Deposit Model: Low-sulfide gold-quartz vein (Cox and Singer, 1986; model 36a).

Mineral List



5 entries listed. 5 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

Becker, G.F., 1898, Reconnaissance of some gold fields of southern Alaska, with some notes on general geology: U.S. Geological Survey 18th annual report, Part 3, p. 7-86. Bittenbender, P., Still, J.C., Maas, K., and McDonald, M., Jr., 1999, Mineral resources of the Chichagof and Baranof Islands area, southeast Alaska: Bureau of Land Management, BLM-Alaska Technical Report 19, 222 p. Cobb, E.H., 1972, Metallic mineral resources map of the Sitka quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-467, scale 1:250,000. Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Sitka quadrangle: U.S. Geological Survey Open-File Report 78-450, 124 p. DeArmond, R.N., 1997, Haleys and Silver Bay, in Around and About Alaska: Sitka Sentinel, series of 29 Articles, April to October, 1997. Loney, R.A., Brew, D.A., Muffler, L.J.P., and Pomeroy, J.S., 1975, Reconnaissance geology of Chichagof, Baranof, and Kruzof Islands, southeastern Alaska: U.S. Geological Survey Professional Paper 792, 105 p. U.S. Bureau of Land Management, 2002, Alaska mineral locations database report (Sitka quadrangle), July 2, 2002, 205 p. [http://imcg.wr.usgs.gov/dem.html]

 
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2020, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: January 24, 2020 18:06:54 Page generated: January 22, 2015 15:08:11
Go to top of page