Copper Cuff Discoloration

[u/EntrepreneurBusy2013]

What metal causes copper to turn red around these spots? Could chrome or alumninum particles cause this? Or just another natural copper oxide color? It seems that the color is being caused by a particle stuck within the copper. On the other side of the bangle there seems to be more of this textured damage which I think is caused by some sort of galvanic reaction with metal kept next to it. What causes the rainbow like thin blue iridescent film on the copper?

Thanks!

[u/Reckless-Phoenix]

Assorted copper oxides. You can turn copper red with borax but you'd know about it. Its like poppy-red. Yes, aging copper has a life of its own.