Australian Natural SOLID Black opal Platinum with diamonds halo ring!! please see photos as part of description! it is approx 5.25 USA size and can be sized up or down by any professional jeweler (the band is thick!). the prongs are long and thick and hold the gem secure, weight approx 6.60g! solid platinum! the diamonds 0.65TCW - marked in the band inside. the opal is approx 10x9mm. it shows the best of its colors under indoor bright light, Sun light - blues and neon blue of different shades! it is high brightness opal! it is solid opal - not triplet not doublet not glued! solid and natural! the face of the ring is 14.8x15.5mm. the photos are close ups to show the details. please refer to measurements in mm and to photos where it is on a hand. hallmark is 850Pt and also tested. solid heavy platinum! in excellent as new condition! the opal has shiny smooth silky surface! no cracks, no damages and no chips! the diamonds are white - baguettes and double halo of round ones! sparkly! the Platinum was professionally polished! looks perfect and gorgeous!! great as everyday ring and especially as October Birthstone! ?fast FREE insured USA shipping and smoke free environment! international shipping available! in perfect condition and comes in a ring case and can be gifted immediately! thank you