Coocoran Opal Field, Lightning Ridge, New South Wales, Australia A solid oval cabochon black opal with true black body color and potch to the reverse side. This is a textbook, classic example of a "nobby" opal (nodule opal) from a renowned old opal claim, with a rich saturation of full spectral colors which are present when the face is viewed full on or from any angle of observation. Weighing approximately 17.17 carats and measuring 22.20 x 15.75 x 7.57mm