A World-Class Gem-Quality Australian Black Opal—"The Stardust Opal". T-Bones Mine, Corcoran, Lightning Ridge, New South Wales, Australia © 2002-2010 Bonhams 1793 Ltd Weighing 14.40 carats and measuring 18.5 x 14.1 x 8.0mm. Sold for $39,650 Found in 1981,...