Commodities
PrimaryCopper
SecondarySilver
Commodity typeM
Deposit
Deposit typeSecondary Enrichment
Model96: Native Cu
Deposit sizeL
Orebody formTABULAR FISSURE
Ore controlFissures and permeable conglomerates and amygdaloidal flow tops
Materials
Ore mineralsCopper, Silver
GangueQuartz, Calcite, Epidote, Pumpellyite-(Mg), Chlorite, Feldspar
Geology
Host rockBasalt,Conglomerate · "Portage Lake Volcanics", "Minnesota Conglomerate"
StructureSyncline, Minnesota fisssure, branch fissure
AlterationBleaching and iron removal; silicification, pumpellitization
Economic & production
Development statusPast Producer
First production1848
Last production1885
Identification
Deposit ID10080378
MRDS IDW031503
Alternate namesMinesota Fissure
RegionNA
Data scoreB
Coordinates46.73028, -89.17563
References
COPPER RANGE CO., UNPUBLISHED, 1968, BEDROCK GEOLOGY MAP OF THE ROCKLAND (NW 1/4) QUADRANGLE, ONTONAGON COUNTY, MICHIGAN. GEOLOGY MAPPED AND COMPILED BY THE COPPER RANGE EXPLORATION CO., INC., AND BY H. HUBBARD (U.S.G.S.)BUTLER, B.S., AND BURBANK, W.S., 1929, THE COPPER DEPOSITS OF MICHIGAN: U.S. GEOLOGICAL SURVEY PROF. PAPER 144,238P.WILBAND, J.T., 1978, THE COPPER RESOURCES OF NORTHERN MICHIGAN; PREPARED FOR THE U.S. BUREAU OF MINES, CONTRACT NO J0366067, 66P.JOHNSON, A.M., AND GROTH, E.H.,, 1998, INVENTORY OF UNDERGROUND MINES, ONTONAGON COUNTY, P. 173-176, MICHIGAN DEPARTMENT OF NATURAL RESOURCES.BUTLER AND BURBANK (1929)