Art Deco black opal and diamond brooch, exceptional solid Australian black opal, possibly lightning Ridge, and diamond brooch set in platinum, opal weighs approx. 6.00 ct and displays strong red and blue/ green colouration in a multi claw setting surrounded by a cluster of diamonds '', total weight of opal 6.00 ct total diamond weight 2.83 carats, total weight 14.6 grams, labels: '.terminating with three vertical bars that are diamond set on a diamond bar