Polhamus NYC "Empire" Coin Silver Butter Knife

Coin silver butter knife in the "Empire" pattern of John Polhamus, NYC. Marked "_[J?]P PATENT 1857" incuse and "GEO. W. CHATTERTON" incuse for the retailer, whose location is unknown. Engraved "Clara 1866" in cursive on the front. Ca. 1857-1866. In very good condition.