The gem variety of the mineral olivine, usually green and yellow-green, was named (1706) from an old French term of unknown origin. Generally, the greener type tends to be called peridot and the yellower type, chrysolite. Although known in biblical times, the source of peridot was the subject of great speculation until the 19th century. One theory was that the gems were from meteorites containing olivine found in Mediterranean countries. it was only early this century that the ancient source was discovered to be the island of Zebirget (known in English as St. John Island) on the Egyptian shore of the Red Sea. Peridot (or olivine, as it is also known) is said to have been one of the stones used in the breastplate of the ancient high priest. It is thought to reduce stress, accelerate personal growth, stimulate the mind and open new doors of opportunity and abundance while banishing lethargy and laziness. it can also help to heal a “bruised” ego by controlling anger or jealousy. It is a good antitoxin stone, cleaning most organs and glands, and an excellent healing stone, acting as a “tonic” to strengthen and regenerate the body. Peridot has been used in the treatment of ulcers and disorders of the heart, lungs, spleen and intestinal tract. It has also been used in the birthing process, thought to stimulate contractions and facilitate the opening of the birth canal. Peridot is one of the birthstones for August (with sardonyx), symbolizing married happiness.