Search:

Cutting up vintage stone would be a bad idea imo.
Personally I like big stones (but that's just preference), but the major reason I think it is pointless is that one way or another, in a couple of...

Based on the color, it could be a dirty belgian blue.
Otoh Belgians are usually a bit wider in my limited experience, so the more probable possibility is a thuringer or escher in a bad state.