Here is a stunning, vintage, solid 10K yellow gold Australian black opal doublet ring. It weighs 3.4 grams and it is a size 8.5 that can easily be sized by a jeweler . It is a large ring, the top measures 21.5 mm across (east to west) or right about .82 of an inch. The featured stone is an absolutely gorgeous black opal doublet which is cut in an organic design and uniquely set. The doublet gemstone was made for structural integrity as opal is a soft stone and in this case the maker used a absolutely gorgeous black opal that simply has amazing rich blue aqua color with flashes of pink, green, yellow and orange color play at every angle when ever the stone moves. A truly a amazing gemstone that has been carefully examined under magnification and it is without scratches or abrasions . The gemstone itself measures approx. 12mm x 9.6 mm. The shape resembles a tulip, wider at one end and tapering down at the other. It is accented with 6 small natural round cut diamonds. The setting is elegant with open gold work and beautiful lines. Stamped 10K and Rost which is not a company or designer I'm familiar with. A beautiful ring which is sure to please, especially as a gift for that special lady.