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Copper - image 2

Copper

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Nicely crystallized native copper on matrix. In good condition. Choice thumbnail for this classic material. The Ojibway Mine, located in Keweenaw County, Michigan, was organized in 1907 and operated underground through thirteen levels before closing in 1913 due to financial and investor challenges rather than a lack of ore. Geologically, the mine is situated within the Keweenaw Peninsula's Precambrian Keweenawan rift sequence, consisting of ancient, tilted basalt lava flows and interbedded sedimentary conglomerates. Native copper mineralization occurs primarily as open-space fillings within amygdaloidal tops of basalt flows and fault zones, accompanied by secondary minerals such as calcite, quartz, and occasional silver.

Product details

SpeciesCopper
SizeThumbnail
Dimensions2.3 x 2.2 x 1.5 cm
Added on09/15/2026
Current owner
Unknown Owner
Acquired
Sep 2026
Previous owners
DateCollectorAcquisition price
—Weinrich MineralsNot disclosed

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Copper
Mineral guide
Learn about Copper
native copper with spinel-twinned crystals and arborescences; notable from Lake Superior, Itauz, Dongchuan, Corocoro, prized for color and localities.
Copper
Regional guide
Copper from Keweenaw County
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Locality guide
Keweenaw County
Keweenaw County, USA - native copper and silver from the Lake Superior district, with sculptural copper crystals and mineral associations for collectors.