The Saginaw Mine was first opened by the Ohio and Isle Royale Mining Company in 1852 when workers sunk a shaft on promising ground. However, the shaft was abandoned shortly thereafter. In 1875, the Saginaw Mining Company organized and erected several buildings for workers, in addition to widening the original shaft and driving a second shaft. When the company agent visited the site in 1878, the shaft work was considered unsatisfactory. By 1879, the site was abandoned and never reopened. Total production from the mine was just over 25 tons of copper ingots.

No trails lead to the site, so access is by boat only. Some piles remain, but are strictly off limits to collecting.

Geology: Small producer. Copper in fissures.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.

ⓘ Copper

Mineral List

ⓘ Native Copper

1 valid mineral.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

ⓘ Basalt

Detailed Mineral List:

ⓘ Native Copper

Formula: Cu

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘ	Native Copper	1.AA.05	Cu

List of minerals for each chemical element

Cu	Copper
Cu	ⓘ Native Copper	Cu

Other Databases

Link to USGS MRDS:	10082643

Other Regions, Features and Areas containing this locality

North AmericaContinent

Lake SuperiorLake

North America PlateTectonic Plate

Mid-continent DomainDomain
Mid-continent RiftNarrow Rift

USA

Midcontinent RiftGeologic Province

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References

Lane, A.C. (1898) Upper Peninsula 1893-1897, Geologic Report on Isle Royale, Michigan. Geological Survey of Michigan: 6(1), 281 pages.

(1902) A Manual of the Copper Industry of the United States and Foreign Countries. The Copper Handbook Vol. 2. Horace J. Stevens

Butler, B.S., Burbank, W.S. (1929) The Copper Deposits of Michigan. U.S. Geological Survey. Professional Paper 144. 238 pp.

Huber, N.K. (1973) Geologic Map of Isle Royale National Park, Keweenaw County, Michigan: United States Geological Survey, Miscellaneous Geologic Investigations Map I-796, scale 1:62,500.

Kaminski-Hamka, T. (2011) The Copper Mines of Keweenaw County, Michigan. Copperlady Press. 150 pages.

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Saginaw Mine, Isle Royale National Park, Keweenaw County, Michigan, USAiRegional Level TypesSaginaw MineMine Isle Royale National ParkNational Park Keweenaw CountyCounty MichiganState USACountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }