HUGE hunk of raw copper...help identifying origin

[jrh4]

Hey guys, so my buddy and I just picked up this giant hunk of raw copper. It weighs around 30 lbs and it's super cool looking, unlike anything I've ever seen. Unfortunately, the previous owner didn't have much of a backstory on it though. All I know is it's from the US. In my research I've found similar specimens (albeit smaller) that came from AZ. So has anyone ever seen anything like this before? I'd love to hear your thoughts....thanks!

 

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[lairmo]

Looks like someone burned a bunch of wiring....IDK

 

[Tony in SC]

I would also say burned wire. Pure copper would have more of a green tint?

 

[pepperj]

Agree with the burnt copper wire, the white residue from the impurities remain on the underneath area. Either it was from a large fire or somebody doing the dirty deed of recovery from insulated wire.
Makes for some cool art though, I have a pieces of welding cable that were made into a Bonsai tree.

 

[brianc053]

jrh4 - You may be aware that large native copper nuggets are found in Michigan; a search for "Michigan copper nuggets" will produce hundreds of images of nuggets found there. But - those images don't look like your pictures of what you have, at least not to me.
Just based on that visual comparison of pictures I'd agree with others who have suggested that your copper hunk is from some other source (not a native nugget).

It still looks cool!

- Brian

 

[Clay Diggins]

It doesn't look like native copper. It looks like the mess left over after an over pour when casting ingots or it could be the dross left over on a pouring crucible lip. The "wires" are drips.

p.s. This would not be a "big" nugget of copper. "Big" is in the multi ton range.

 

[releventchair]

Thee is at least one mine in AZ. that uses Michigan samples to show visitors.
Az. copper is pretty much dust. The processing of it interesting...

 

[jrh4]

very cool bonsai pepperj! thanks for the feedback everyone. that all makes total sense. cheers!

 

[galenrog]

Based on the images provided, I think Clay is most likely correct.

Having found many examples of native copper, color and texture are wrong. At least in my experience. While color is similar to burned copper plate, again, texture is not quite what I would expect.

I would lean in the direction of an over pour, rather than dross, although a physical examination could easily change my mind. Dross should show more impurities than what appears.

As far as remains of a mass of burned wire or cable, too many things wrong visually. to achieve temperatures high enough to burn off all carbon, the copper would be left extremely brittle, leaving one to expect broken surfaces on your piece.

Time for more coffee.

 

[islamoradamark]

good pic up