Who knew that printmaking with plaster was a thing? In this video, Graham of Diode Press uses nothing but plaster of Paris, a copper plate mezzotint, and ink to create a lovely print piece. He writes:
I’ve come across this method over the years in various articles and by word of mouth and I’d definitely recommend giving it a try! This works with linocuts, etchings, aquatint, or even woodcuts (if you seal the wood first), and requires no press, Barens, or even paper!
I’d test it out on an old plate before trying it on something you care about, in case it does not work out how you’d expect or damages the printing matrix.