Wear topaz only if you wish to be clear-sighted as legend has it that it dispels all enchantment and helps to improve eyesight as well!
The ancient Greeks believed that it had the power to increase strength and make its wearer invisible in times of emergency. Topaz was also said to change color in the presence of poisoned food or drink. Its mystical curative powers waxed and waned with the phases of the moon.
Perhaps the most famous is a giant specimen set in the 17th century Portuguese Crown, (1,640 carats) the Braganza as it was named, was first thought to be a the largest diamond ever found, later it was discovered to be a colorless topaz.