patina /(păt"ĭ*nȧ; It. pä"tē̇*nȧ)/

pat·ina

patina

n.
  1. A dish or plate of metal or earthenware; a patella.
  2. The color or incrustation which age gives to works of art; especially, the green rust which covers ancient bronzes, coins, and medals. (Fine Arts)