I found that since the addition of the coinage mold, it seems that it has not been completed, because it can only produce square coins, rather than round coins found in the dungeon, and the tooltip mentioned to change the shape of the mold with a chisel has always been in the WIP state, so will this be repaired（ Although it’s just an entertainment that doesn’t have much to do with gameplay.)
The real Problem this thing has is you cant really chisel it because even if I made it full block size, clicking with your Mouse onto the thing will not work properly at that level of precision. That’s why it has been left abandoned forever.
But you can try another method: use the chisel to right-click to switch fixed modes (square, coin pattern in dungeon or other patterns) instead of custom patterns like molds. Although this is a bit unreasonable, it can at least get coins like dungeon