This is an unusually-shaped, screw-top sugar shaker, caster or sifter with a hand hammered finish. It's made from leadless English pewter and so is safe for food use.
It has a screw top which works well and large holes, to prevent clogging.
The maker's mark on the base reads: "English hand hammered pewter 917". We'd think it's from the first half of the 20th century.
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