Oval Opal Pendant Micallef Jewellers 14K Oval Opal Diamond Necklace Diamond Necklace Natural Opal Opal chain pendant, opal pendant silver, Australian opal pendant, opal Opal Oval Pendant Necklace in Platinum at 1stDibs. Includes: A matching box. Style: Modern Material: 925 sterling silver, platinum plated, opal Care: Avoid wearing during exercise, as sweat will react with the jewelry to produce silver chloride and copper sulfide, which causes the jewelry to deteriorate and corrode over time. Imported Gemstone origin: Australia Product measurements: Chain length: 15. 7 in Extension chain length: 2 in Weight: 0. 07 oz (2 g)