I'm surprised that nobody has looked at the similarities and differences between stone moulds, for casting copper and bronze, and rock art, from the same, or similar, period.
No - that's just waffle. I may be asking you to look under the chili bush early next week but - can anyone find a photograph of the inside of a beaker, please? I'm looking for the inside base, ideally. Most pictures just concentrate on the incised and impressed external decoration usually.