Thank you Adam, very helpfulHello,
it’s gold plated brass with a layer of colored lacquer. The orange spots are most likely lacquer, there should be an extremely fine layer of gold beneath, the rest is pure brass. The red spots are copper, something dissolved the zinc from the brass alloy. It can be polished out, if it won’t go away, it’s deep and could cause problems for eg. during a replate (it rarely happens).