is this a cannonball? Not perfect spherical solid metal object that measures 9 cm and weighs 3671 grams.
I would think it is (just my guess) But looks to be in overall very good condition.Must have been ‘cleaned’
Since it looks as though something may have broken off a bit, you might look at ball gate weights too.
Maybe it was originally part of a chain shot? Something like. https://www.worthpoint.com/worthopedia/revolutionary-war-era-chain-shot-2007308261
Fly press weight? This is a British cannon ball table, it give the sizes and weights. https://www.arc.id.au/Cannonballs.html