What does an opal symbolize? Opals have traditionally symbolized hope, purity and truth and they are the stone given to celebrate the 14th wedding anniversary. In ancient times the opal was a stone of fidelity and assurance, and was often worn as an amulet, to bring about loyalty and faithfulness. This Hexagon shaped piece of Opal measures 3cm x 3cm approx and is suspended from a 19 Inch 925 Silver chain. October Birthstone. Those born in October enjoy two spectacular birthstones to commemorate their birthdays – Opal and Tourmaline. Both October birthstones have endless colour combinations and beautiful colouring characteristics.