I would say no older than 1930 but more likely mid century !! See the large hole on the bottom ?? That is to keep it from exploding in the kiln !! Before 1920 or about they used a very small hole !! The large hole is a modern manufacture !! And as I said in another post,, the foot does not show the wear it should have for that date !! Remember that foot is unglazed and porous,, it will absorb anything in the air !! I do not care how clean one tries to be ,, that is unavoidable !! Even when one dusts today,, rarely do they touch that part of pottery !!