Mine detail: Pewabic Amygdaloid

Previously called 'Pewabic LodePewabic Amygdaloid Lode'

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Location

Lat / long: 47.13333, -88.56672

Resource(M)

Primary: Copper
Secondary: Silver
Ore: Copper, Silver
Gangue: Quartz, Calcite, Pumpellyite-(Mg), Epidote, Chlorite
Orebody form: AMYGDALOIDAL LODE

Production

Operation type: Underground
Production size: Large
Development status: Past Producer
Production years: VARIOUS MINES INTERMITTENTLY PRODUCED FROM THIS AMYGDALOID FROM 1857 AT LEAST THROUGH 1925. ALL REMAINING MINES IN DISTRICT CLOSED IN 1968
First production started: 1857
Last production ended: 1931

Geology

Host rock:Portage Lake Volcanics
Host type:Andesite
Structure:Hancock fault
Alteration processes:Oxidized and bleached

References

MRDSW060039
DEP10082606
Reference{Deposit:: BUTLER, B.S., AND BURBANK, W.S., 1929, THE COPPER DEPOSITS OF MICHIGAN: USGS PROF. PAPER NO. 144, 238 PP.}{Deposit:: WEEGE, R.J., AND POLLACK, J.P., 1971, RECENT DEVELOPMENTS IN THE NATIVE-COPPER DISTRICT OF MICHIGAN: IN W.S. WHITE, (EDITOR), GUIDEBOOK FOR FIELD CONFERENCE, MICHIGAN COPPER DISTRICT, SEPT. 30-OCT. 2, 1971, PP. 19-43}{Deposit:: WHITE, W.S., 1968, THE NATIVE COPPER DEPOSITS OF NORTHERN MICHIGAN: IN J.D. RIDGE, (EDITOR) ORE DEPOSITS OF THE UNITED STATES 1933-1967 (GRATON-SALES VOLUME); AM. INSTIT. MIN. METALL. PETROL. ENG., V. 1, P. 303-325}{Deposit:: CORNWALL, H.R., AND WRIGHT, J.C., 1956, GEOLOGIC MAP OF THE HANCOCK QUADRANGLE, MICHIGAN: USGS MAP MF-46, SCALE 1:24000.}{Deposit:: BODWELL, W.A., 1972, GEOLOGIC COMPILATION AND NONFERROUS METAL POTENTIAL, PRECAMBRIAN SECTION, NORTHERN MICHIGAN: HOUGHTON, MICHIGAN TECHNOLOGICAL UNIVERSITY, M.S. THESIS, 98 P.}{Deposit:: BORNHORST, THEODORE J., 1992, KEWEENAWAN COPPER DEPOSITS OF WESTERN UPPER MICHIGAN; AN OVERVIEW OF THE KEWEENAW PENINSULA NATIVE COPPER DISTRICT, MICHIGAN: GUIDEBOOK SERIES, VOL. 13, P. 33-62.}{Production:: WEEGE AND POLLACK, 1971 WHITE, 1968}
ReporterNicholson, Suzanne, Sutphin, D.M., Mason Jr., G.T., Woodruff, Laurel G.