Opals can be found all around the globe, due to unique geological formations, but Australian opals have the reputation of being the highest quality and most expensive in the world. Marked by brilliant ribbons of fire in every color of the spectrum, they account for 95% of the world’s supply. Because of their rarity, Australian opals have become an increasingly popular choice, not only for those who admire their unique patterns and glowing inner beauty, but also for smart investors.