Thanks for your response, Joe, I've scrubbed on them enough, and polished enough, and finally put them back in the machine, and I don't remember seeing any part no. on them, but in the "what do you know" dept. When I scraped all the rust off of the bentwood case key, there WAS a very tiny part no. on it. Made my day. Still can't decide why these plates are so dark unless someone washed them in a dishwasher. I have some aluminun knives that got dark that way. BTW...we just moved this year from Quad Cities to sunny (hot) south for the rest of our retirement. Loving it.