"Estimated at 80,000-100,000 pounds, this unique piece, complete with its envelope embossed with the White Star Burgee, was written by Second Class passenger Esther Hart, the mother of the famous survivor Eva Hart, and it is featured in Eva Hart's biography 'Shadow of the Titanic'," the Auctioneers said in a statement. Hart, whose mother Esther had written the letter, was travelling with her parents to Canada to start a new life.