The ancient Phasael Tower in the Tower of David complex in Jerusalem has a big crack in it, which poses a danger to the whole tower. It is under repair. The coin was found there in a misplace box of artifacts excavated during the last conservation in the 1980s. Oops.
Some PaleoJudaica posts on the Tyrian shekel are here, here, and here. It was especially associated (in its full and half value denominations) with payments to the Temple, including the Temple tax.
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