Sotheby's famed auction room was filled with gasps followed by shocked silence after an iconic statue priced far too ambitiously failed to sell at auction. Billionaires descended on the New York City event on Tuesday in the hope of snagging a masterpiece created by the likes of Picasso, Monet or Matisse. But it was Alberto Giacometti's 1955 bronze bust, called Grand tête mince, that was billed as the auction's centerpiece by experts who gave it a $70 million guide price.