Definition of petition crown in English:

petition crown

noun

  • A trial piece for a five-shilling coin engraved by Thomas Simon as part of a contest between himself and the Roettiers brothers to decide who would engrave the dies for the new mechanized coinage of Charles II, having Simon's petition for preference engraved on the edge.

Origin

Mid 18th century; earliest use found in Stephen Martin Leake (1702–1773), herald and numismatist.