Yep, sorry, it's not "copper coloured", it's just brown, probably from tannic acid staining from soil. You can see on the "high points" the brown colour has worn away, showing the grey metal underneath, so I'm guessing it spent some time underground, then was dug up and went back into circulation for a while.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis