The 34.40-carat Stotesbury Emerald, a six-sided gem with a famed history that spans more than 100 years, headlines a cavalcade of magnificent jewels at Sotheby's New York on Tuesday. The Colombian-mined emerald was previously in the collections of three high-profile American jewelry collectors: Evalyn Walsh McLean (1908), Eva Stotesbury (1926) and May Bonfils Stanton (1947). […]