Unlined copper coffee roasting pan
Probably. From what I read copper is reactive with acids, but coffee is rich in alkaloids, which as the name suggests, are alkaline. And there's no water involved, so no easy way for copper ions to migrate into your beans. But be sure to give the pan a good scrub with vinegar and salt to remove any those bluish copper oxides, which might flake off and make your coffee taste nasty.