Donate now to keep alive!Help|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
What is a mineral?The most common minerals on earthMineral PhotographyThe Elements and their MineralsGeological TimeMineral Evolution
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Manganese Mine, Copper Harbor, Keweenaw Co., Michigan, USA

This page is currently not sponsored. Click here to sponsor this page.
Location is approximate, estimate based on other nearby localities.
Latitude & Longitude (WGS84): 47° North , 87° West (est.)
Margin of Error:~4km
Other regions containing this locality:Keweenaw Peninsula, Michigan, USA
Köppen climate type:Dfb : Warm-summer humid continental climate

The Manganese Mine is one of the more interesting mines of the Keweenaw. Manganese minerals were discovered south of Copper Harbor by geologist Douglass Houghton in the 1830s. In 1881, an open cut to a depth of 75 ft. was mined by the Cambria Iron Co. and approx. 800 tons of material was removed. In 1883, a shaft was sunk and another 400 tons of manganese ore was removed for assay. It was determined that the ore was unsuitable for steel production, and the mine was abandoned.

The piles, if found through 120 years of overgrowth, can produce some excellent micro-minerals. It is the only site on the Keweenaw where specimens such as orientite, braunite, and macfallite are found.

Mineral List

24 valid minerals. 1 (TL) - type locality of valid minerals. 1 erroneous literature entry.

This page contains all mineral locality references listed on 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 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.


Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Mineralogical Magazine (1979): 43: 325-331.
Rocks & Minerals (1983): 58: 111.
Blaske, Allan R., Theodore J. Bornhorst. Allan M.Johnson, Gordon E. Rantti and Robert C. Reed (1988), Manganese Investigation in Keweenaw County, Michigan, Michigan Geological Survey Division, Open File Report OFR 88-2, 36 pages, 0 plates.
Nickel & Nichols (1991), Mineral Reference Manual: 124.
Heinrich & Robinson (2004), Mineralogy of Michigan.
Clarke, Copper Mines of Keweenaw, USGS Professional Paper 144.
Rosemeyer, T. (2014): History and Mineralogy of the Manganese Mine, Keweenaw County, Michigan Rocks & Minerals 89, 498-515.
Carlson, S.M., Olds, T.A., Rascona, J., Smith, A.E. (2014) A new locality for volborthite from the Manganese Mine, Copper Harbor, Michigan. Mineral News, 30(2): 1 ff.

External Links

Mineral and/or Locality is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © and the Hudson Institute of Mineralogy 1993-2018, except where stated. relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: January 21, 2018 05:10:11 Page generated: January 3, 2018 08:27:34
Go to top of page