This is a black opal pendant top. It has a simple design with a zirconia-studded frame, and displays various play-of-color such as red, blue, and green. It's a deep blue like the ocean and is very beautiful. It's even more beautiful when seen with the naked eye than in the photos... This one is blue-based with prominent green play-of-color. I have other items for sale, so please take a look! Black Opal → Oval cabochon Setting → silver925, zirconia Loose stone size: Approximately 10mm x 7mm Please note that this was not measured with a dedicated instrument.