Blue Opal 9ct Gold RingStunning ladies 9ct yellow gold ring Set with an oval shaped Synthetic blue opal stone in rub over setting This ring can also be made in white gold on request The October birthstone, opal is also commonly given as the 14th wedding anniversary gift The concept of birthstones is age old and wearing your birthstone is thought to bring good luck. Opal is a stone that refracts a Kaleidoscope of colours when slightly altered in the light.