As part of the customary fashioning process, virtually all rubies are heated to permanently improve their color and appearance. The finest rubies emanate from Burma, having been mined there since ancient times. Other sources include Thailand, Vietnam, Sri Lanka, Kenya, Tanzania, Cambodia, Afghanistan and India. It is also the anniversary gemstone for the 16th year of marriage. Peridot should be a lively lime green, without a brownish or olive cast.
Peridot is the child of volcanic action.
Tiny peridot crystals are sometimes combed from the black sands of Hawaii. Peridots were favored by pirates, considered powerful amulets against all evil, and when set in gold, were said to protect the wearer from the terrors of the night. They had medicinal uses, too. If fashioned into a chalice from which medicines were drunk, they intensified the effects of the drug. Protect the peridot from scratches, sharp blows, household chemicals and extreme temperature changes.