Michigan!

A great, exceptionally well crystalized copper specimens form one of the older and more obscure Michigan copper mines.  The Pewabic Mine operated from about 1855 until 1884, and was later incorporated into the Quincy Mine.  The piece features numerous very sharp crystals on a matrix of more massive copper, with a great patina that does not appear to have been affected by the usual cleaning with acid.  

A large and very sculptural copper specimen from the site pine mine, displaying well formed crystals throughout it's length.  Although the White Pine Mine produced a lot of specimens, the bulk of them tend to be flattened crystals with a notably two-dimensional appearance-- good, more 3D specimens like this are considerably more hard to come by.  You do have the flattened areas typical of White Pine, though this seems to have had much more space to crystalize, as it is covered with crystals.  This piece even has a drill scar present-- I do not know enough about the various mining implements used to be able to hazard a guess as to when this occurred, though the mine operated intermittently between 1880 and 1974. Regardless of when it was found, it remains a very large and dramatic piece-- it'd even call it a "statement copper" for a shelf, even surrounded by other copper country minerals, with quite a bit of bang for your buck.  I do think this one displays better in person... it's hard to capture a nearly 40 cm specimen in a small image. You can get a sense of what I mean by looking at the closeups.

A very beautiful matrix specimen of copper in calcite, from the Quincy Mine in Michigan's Upper Peninsula. These are probably one of the more iconic items from the region, and because of the relative fragility of the calcit,e something that has become much more uncommon than the copper specimens that continue to be collected of the old mine dumps. 

A very scultural group of copper crystals from Michigan's upper peninsula. There is something very satisfyingly chunky about the individual crystals, yet they still display good faces and are arranged in a pleasantly loose, three-dimensional form.  Can be displayed form multiple angles.  

When it comes to Michigan copper, I am quite picky.  There is a nearly endless supply of twisted chunks and bits-- occasionally you will get a crude crystal that must be half-way imagined, or a crystal random face. But I like the sharp ones-- the specimens that leave no doubt that what you are looking at is in fact a copper crystal. This one fits the requirement, with a cluster of elongated crystals rising out of a matrix of more copper crystals. The chocolaty patina is particularly good one this one. 

A great example of "the other style" of Quincy copper in calcite specimens-- this is a colorless crystal with the copper not interspersed throughout the calcite, but rather with the calcite crystalized over a thicker growth. In the case of this piece, the copper gives a sort of nest/ cradle like appearance, with the colorless calcite nicely positioned in the middle.  

A copper specimen shaped like a rabbit-- though it has a 3rd ear. I really like this piece, it so clearly looks like something else-- and the crystals are quite sharp as well. 

A very rare and unusual specimen from Michigan's "Copper Country."  Everyone has seen the iconic copper in calcite specimens, but how often do you see copper in quartz?  This piece has sheet-like copper growths interspersed between quartz growths with varying degrees of crystallization, in some areas you can even see the copper inside the quartz crystals-- admittedly not the most finely crystalized-- but with the familiar copper gleam you would see in the included calcites. A very unusual piece!

A copper specimen from one of the most difficult to obtain of the various Michigan copper localities. Unlike almost all the other specimens that came from old mines or the waste piles that they left behind, this location was discovered in the early 90's by local collectors scouting land that had been cleared for logging roads.  This place is pretty much at the end of the Keweenaw peninsula, just a couple miles from where it juts out into Lake Superior-- in fact I know of only one other locality (that is not an island) past it-- that would be Keweenaw Point, where they find the yellow datolites.  This locality is notable for producing some of the largest copper crystals found in Michigan, and while these are certainly not that size, it remains a very well crystalized specimen with crystals that reach 5 cm in length.  To give a sense of rarity, there are only 2 other examples from here pictured on MinDat. 

A skeletal group of copper crystals from one of the most difficult to obtain of the various Michigan copper localities. Unlike almost all the other specimens that came from old mines or the waste piles that they left behind, this location was discovered in the early 90's by local collectors scouting land that had been cleared for logging roads.  This place is pretty much at the end of the Keweenaw peninsula, just a couple miles from where it juts out into Lake Superior-- in fact I know of only one other locality (that is not an island) past it-- that would be Keweenaw Point, where they find the yellow datolites.  This locality is notable for producing some of the largest copper crystals found in Michigan, and while these are certainly not that size, it remains a very well crystalized specimen.  To give a sense of rarity, there are only 2 other examples from here pictured on MinDat. 

A nice example of quartz over a thin layer of chrysocolla. The piece was simply ascribed to "Bisbee" but I suspect this is from the Bagdad or Ray Mine (neither is in Bisbee)

An unusual, old Michigan specimen from the Upper Peninsula-- a pseudomorph of chamosite after (most likely almandine) garnet, on matrix.

An unusual, old Michigan specimen from the Upper Peninsula-- a pseudomorph of chamosite after (most likely almandine) garnet, on matrix.

An unusual, old Michigan specimen from the Upper Peninsula-- a pseudomorph of chamosite after (most likely almandine) garnet.

For the sake of variety, this ugly thing is a sample of the rare copper sulfide anilite (Cu7S4), from the Champion Mine, in the lower portion of the Keweenaw Peninsula. The area is most famous for its coppers, silvers, and datolites, but there actually are a number of other minerals that occur there-- some quite rare. A few have even been discovered there-- it think about 6 or 7 (mostly copper bearing, go figure) between Houghton and Keweenaw Counties, which account for the bulk of the Keweenaw peninsula portion of the greater Upper Peninsula (it's a peninsula on [in?] a peninsula.... I was completely confused about this as well until the local hotel guy set me straight.)