Present in Michigan County: Marquette, Keewenaw; Geological Formation: Neguanee Fm., Veins in Portage Lake Lavas and Copper Harbour Conglomerate; Specific Mine Name: 1881-1883 (Manganese Mine), 1917-1963 (by product of some Iron Mining); Commercial Mining History: 1881-1883 (Manganese Mine), 1917-1963 (by product of some Iron Mining); Published Literature: BLASKE, A.R., BORNHORST, T.J., JOHNSON, A.M., RANTTI, G.E. & REED, R.C.,1988, Manganese Investigation in Keweenaw County, Michigan. Michigan Geological Survey Open File Report, 88-2. 12p.; Unpublished Literature: Babcock,1974, Mineralogy, Geochemistry and Genesis of the Magnetite-Jacobsite Mineral Series and Manganese-Ferrite-Bearing Iron Formation from Champion Mine, Champion, Michigan, [...]
