David K. Joyce Minerals

Copper, Keweenaw Peninsula, Michigan, USA

The Keweenaw Peninsula of the upper peninsula of Michigan State was one of the premier producers of copper. Not on;y were astounding tonnages of copper produced but many fantastic specimens of native copper, sometimes crystallized, were produced. The mines of the Keweenaw Peninsula were mostly underground mines that tapped either humongous deposits of copper in conglomerate/basalt strata or large fissure veins. The fissure veins were the source of most of the crystallized copper specimens that you see. The conglomerate and basalt were the source of amygdaloidal copper, Copper "skulls", and sheet copper. The geology, mineralogy and history of the "Michigan Copper Country" is fascinating and you can learn more about it in the special "Michigan Copper" issues of "Rocks and Minerals", Volume 77, No.6 or The Mineralogical Record Volume 23, No. 2. Each a fantastic publication.

All prices in Canadian dollars. For payment in US$, deduct 20% or multiply by 0.8.

Click on any of the following thumbnails to view a larger image of the specimen.

CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #12339
  • Copper
  • 8.2x5.0x4.0 cm
  • Largest Crystal Size: n/a
  • $30.00
  • Ontonagan Co.
  • Keweenaw Peninsula
    Michigan, USA
  • A sculptural specimen of copper with quartz crystals embedded in it , mostly on the bottom. Heavy!
Copper/SilverCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11842
  • Copper/Silver
  • 2.9x1.9x2.0 cm
  • Largest Crystal Size: s-4,5mm
  • $40.00
  • Evergreen Bluff Mine
  • Ontonagan Co.
    Michigan, USA
  • A nice, hackly aggregate of copper with a silver crystal attached to the top of it. Excellent example!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11837
  • Copper
  • 4.1x3.2x1.7 cm
  • Largest Crystal Size: 10mm
  • $75.00
  • Phoenix Mine
  • Keweenaw Co.
    Michigan, USA
  • Nice parallel-growth group of copper crystals with some quartz attached. Looks great!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11834
  • Copper
  • 5.4x5.2x4.2 cm
  • Largest Crystal Size: 28mm
  • $50.00
  • Wolverine Mine
  • Houghton Co
    Michigan, USA
  • A very sculptural group of copper crystals protrudes from a calcite vein on the side of amygdalodal basalt. Nice looking specimen! Classic.
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11830
  • Copper
  • 5.3x2.0x0.8 cm
  • Largest Crystal Size: 40mm
  • $60.00
  • Phoenix Mine
  • Keweenaw Co.
    Michigan, USA
  • This specimen shows one long copper crystal with a number of blockier crystals attached to one end. Great shape! Great example of copper crystals.
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11824
  • Copper
  • 3.5x1.4x1.3 cm
  • Largest Crystal Size: 20mm
  • $40.00
  • Phoenix Mine
  • Keweenaw Co.
    Michigan, U.S.A.
  • I think this could be one elongated, full crystal of copper with some off-shooting twinned crystsals. A little calcite attached. Classic!
Copper/SilverCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11823
  • Copper/Silver
  • 2.2x1.7x0.8 cm
  • Largest Crystal Size: n/a
  • $35.00
  • Osceola Mine
  • Houghton Co
    Michigan, USA
  • A cute little "nugget" of copper with an imiscible phase of silver. Excellent example!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #12356
  • Copper
  • 3.7x4.2x2.3 cm
  • Largest Crystal Size: 26mm
  • $35.00
  • Keweenaw Peninsula

  • Michigan, USA
  • This specimen sports a bright, elongated, twinned crystal of copper protruding from basalt matrix. Looks great!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #10197
  • Copper
  • 9.9x2.4x0.6 cm
  • Largest Crystal Size: 6mm
  • $30.00
  • White Pine Mine
  • Ontonagon County
    Michigan, USA
  • A spindly, dendritic cluster of distorted crystals. Interesting specimen!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #10228
  • Copper
  • 3.1x2.2x1.4 cm
  • Largest Crystal Size: 18mm
  • $60.00
  • Mass Mine
  • Ontonagon County
    Michigan, USA
  • A lovely stack of complex copper crystals with a thin black coating of, probably, tenorite. Nice specimen!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #10248
  • Copper
  • 10.3x3.0x2.5 cm
  • Largest Crystal Size: 85mm
  • $225.00
  • Keweenaw Peninsula

  • Michigan, USA
  • A classic keweenaw copper crystal specimen consisting ofone large distorted crystal with some smaller crystals attached. Classic! Displays well.
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #10249
  • Copper
  • 5.0x4.0x2.7 cm
  • Largest Crystal Size: 52mm
  • $190.00
  • Keweenaw Peninsula

  • Michigan, USA
  • A single, large crystal of copper with quartz-epidote matrix. The quartz epidote matrix is partially covered with small, sparkling quartz crystals. Interestinglu, the copper crystal is two thirds thinly covered with a red copper oxide (cuprite?) while the other third has a thin veneer of black copper oxide(tenorite?). Very nice, classic Keweenaw specimen!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #10250
  • Copper
  • 6.2x5.2x1.7 cm
  • Largest Crystal Size: 34mm
  • $225.00
  • Keweenaw Peninsula

  • Michigan, USA
  • A nice looking cluster of copper crystals with one large crystal sticking up out of the rest. Good looking piece of distorted copper crystals from this famous copper mining area. Displays well!
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #12221
  • Copper
  • 6.8x4.9x1.9 cm
  • Largest Crystal Size: 32mm
  • $85.00
  • Keweenaw Peninsula

  • Michigan, USA
  • A cluster of several large, elongated crystals of copper. The crystals appear to be distorted dodecahedra and have sharp cubic crystal overgrowths on many of the crystal faces. Nice!
Copper, PrehniteCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11976
  • Copper, Prehnite
  • 8.4x5.2x5.4 cm
  • Largest Crystal Size: 25mm wires
  • $225.00
  • Champion Mine
  • Houghton Co.
    Michigan, USA
  • Here is a super specimen of native copper. This specimen shows a vug in prehnite and quartz, with some of the calcite etched away that reveals excellent wires of copper. Displays perfectly!
Copper, CalciteCopper, Keweenaw Peninsula, Michigan, USA
  • Item #11357
  • Copper, Calcite
  • 4.2x2.4x2.5 cm
  • Largest Crystal Size: c-18mm
  • $110.00
  • White Pine Mine
  • Ontonagon County
    Michigan, USA
  • This branching aggregate of dendritic copper crystals has a couple of colourless scalenohedrons of calcite attached to the top of it. The calcite crystals are very well formed, singly-terminated crystals. Striking specimen!
Copper, SilverCopper, Keweenaw Peninsula, Michigan, USA
  • Item #15066
  • Copper, Silver
  • 9.0x3.3x0.9 cm
  • Largest Crystal Size: n/a
  • $45.00
  • White Pine Mine
  • Ontanagan Co.
    Michigan, USA
  • This oblong shaped glob of native copper is laced with native silver, particularly at on end. A classic "half-breed" nugget in the parlance of the Upper Peninsula copper country.
CopperCopper, Keweenaw Peninsula, Michigan, USA
  • Item #17430
  • Copper
  • 6.4x2.6x1.2 cm
  • Largest Crystal Size: 14mm
  • $80.00
  • Keweenaw Peninsula
    Michigan, USA
  • This is a really nice copper specimen showing fairly well-formed copper crystals in a branching, solid copper aggregate. Too bad we don't know the exact locality. Displays very well!!