cast curling stone

Here is a special item for wich i did not really found any real possible identification. This is a cast curling stone made of steel and brass,weights a good 20 pounds and marked under John Bradwood & sons Montreal and the number 23. There are also on the front i believe M.S.J. this could be a foundry mark but nothing on it in Montreal eighter. This could be a door stopper or else.If you have any idea this will be welcome.

cast curling stone 1

cast curling stone 2

cast curling stone 3

cast curling stone 4

cast curling stone 5

cast curling stone 6

cast curling stone 7