Crest of Mercury

The Crest of Mercury is an item obtained in Silent Hill. Harry Mason can find the crest inside a broken jewelry case in the jewelry store on the second floor of Nowhere. The Crest of Mercury, along with four other items, must be used in order to unlock the final door in Alessa Gillespie's room.

Silent Hill: Book of Memories
The Crest of Mercury is an obtainable artifact. It is described as, "An iron rod, shaped for the Roman messenger god."

Trivia

 * The crest is named after Mercury, the Roman messenger god. The shape of the crest offers room for confusion, as it is a combination of Mercury's staff (the Caduceus) and the symbol for medicine (the Rod of Asclepius).