Australian Black Opal 16.5x8mm Pendant set in 583 14K Yellow Gold - Blue-Green with 25 RBC diamonds G/VS TW=0 Classified by the Opal industry as Natural Opal Type 1 Genuine Australian Black Opals are the most valuable and popular of all Opals and account for around 5% of Opals and is found at Lightning Ridge in Northern New South Wales. https://vimeo.com/227208275