The popular superstitions concerning gems are survivals of the ancient custom of wearing amulets. An amulet (from the Arab word hamala, "to carry") is anything hung around the neck, wrists, ankles, or in any way attached to the person for the purpose of warding off evil or protecting against illness. For many individuals, the gem amulets of modern times carry the same powers to deflect the evil eye or other negative forces as they did in the days of the pharaohs.
Amber is one of the oldest of all gem amulets. Because it is said to change color with the state of one's health, it is an excellent indicator of one's physical condition. There is also a belief that amber has the power to prevent illness, and that it will provide a special protection against throat problems if it is worn on a ribbon around the neck.
Coral also is said to change color according to the state of one's health. An old tradition instructs mothers to hang an amulet of coral around an infant's neck to save it from falls and illness. During the Middle Ages, coral amulets were worn as protection from evil wrought by witchcraft.
For centuries, opals have been thought to be lucky gems and to possess supernatural powers.
The sapphire has also been a symbol of good luck since the most ancient of times. The Greeks believed that to wear the sapphire was to invite the favor of the gods. The diamond was also considered lucky, particularly among the Romans.
In many Arabian countries the favorite good-luck amulet is turquoise, which is often engraved with the name of Allah or a verse from the Koran.
While certain people believe that pearls bring bad luck, the Romans and Greeks wore pearls to win the favor of the goddess Venus. Asians generally esteem pearls to have medicinal properties and believe that to wear them greatly improves the clearness and beauty of the skin.
The custom of wearing one's birthstone as a lucky gem still exists. Following are the birthstones that are traditionally believed to bring good luck to the wearers: January, garnet; February, amethyst; March, bloodstone; April, diamond; May, emerald; June, agate; July, ruby; August, sardonyx; September, sapphire; October, opal; November, topaz; December, turquoise.