For Thousands of Dollars A London gallery is selling Johnny Depp’s Heath Ledger and Bob Marley silk-screen prints for thousands of dollars. Castle Fine Art is selling the four-piece “Friends & Heroes II” collection, signed by Depp, for £17,500 ($21,000). It has portraits of Ledger, Marley, River Phoenix, and Hunter S. Thompson. Two weeks ago, the portraits sold for $5,400 each, but all 780 prints sold out. Currently, Depp is working with Al Pacino on the biography of Italian artist Amedeo Modigliani. Depp will be directing for the first time in twenty-five years. Are you an art collector? What is one way people can identify a worthy piece of art?