I hand-picked this pretty 4.3ct Welo opal and had it set in a custom made 14k yellow gold setting. The back of the ring shows through this opal creating a cool leopard spot effect. Ring face measures 18.6mm x 12.25mm. Ring size 6.
Side note: Welo opals are hydrophane opals, while much hardier than Australian opals, you must keep them dry (i.e., take off while swimming, showering) because they will absorb any liquid including water and it will cloud them, sometimes permanently.