I'm new here. Could someone please help me identify the date of this William III halfpenny, if that's possible? The date has worn off the reverse. The coin is 27mm in diameter, and I don't know its weight. Text on front: GVLILLMVS TERTIUS (with dot). Text on back: BRITANNICA (with dot). The coin isn't magnetic.
Thank you!
PS The coin belonged to my grandfather
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