Fire opal and diamond ring, circa 1915. Fire opals are an unusual variety of opal, found primarily in Mexico. Popularised in the 19^th century, fire opals only occasionally show the rainbow iridescence associated with most opals, but more than make up for it with their distinctive and highly attractive body colours, ranging from a glowing orange to a deep cherry red. The cabochon fire opal at the centre of this ring is of superb quality – of impressive proportions, a deep, fiery orange and and excellent clarity, framed beautifully by an early 20th century yellow gold mount with fleur-de-lis shoulders and a delicate border of charming cushion-shaped diamonds.