Are original brass lamp socket only brass electroplated?

[Count Orlock]

I was polishing the brass from a train, and when I went to polish the brass lamp sockets, the brass wore off and silver metal was visible. Does that mean that it is a reproduction? I thought that Lionel brass trim and parts were solid brass.

[David1005]

Not sure what engine or era we are talking about here. If this is prewar tin plate the stamped trim parts were brass.  If it is a cast headlight, I think they were die cast zinc and painted gold or brass.