Cannonball mould, maybe

This item was in the gun auction I’ve attended today. Here is the official description: UNITED STATED NAVY CAST IRON 3 POUND BOARDING GUN CANNONBALL MOLD, SIGNED DELANG EVERETT 4-27-33, MOUNTED ON SHIP’S PLANK BASE (ESTIMATE $500-$800)

Does this sound true to anyone? Remembering my “cannonball” which is actually a commercial deep sea fishing net weight sink, I have my doubts.

Assuming it does cast a round ball, I would think this might be a mold for a fishing weight as you have suggested. I suspect the date on it is 1933, as its construction looks too ‘modern’ to be an original mold for a Navy cannonball. In addition, that plank base would not last too long if it actually was intended for casting iron balls.