Peridot, Birthstone for August
Peridot is the birthstone for August. It is the gem-quality transparent variety of olivine, a mineral composed of magnesium iron silicates. Peridot is formed in the mantle deeper than the earth’s crust and is brought to the surface through volcanic action. Scientists are planning to drill through the crust to the mantle to retrieve fresh mantle peridotite in order to study mysteries as to the earth origins. This sample would be a geochemical treasure trove to study. Scientists are scouting spots near Costa Rica, Baja California and Hawaii. Some of the beaches of Hawaii, the sand is interspersed with tiny peridot.
The word peridot comes from the Arabic “faridat,” which means, “gem.” The color for peridot ranges from olive to lime green. The iron content colors the gem green, the more iron the more olive the gem. Some of the finest peridot has been mistaken for emerald. Cleopatra’s famous emeralds may have been peridot. The Egyptians called it the Gem of the Sun and mined peridot Red Sea island of Zabargad. This is the source for many of the large peridot in museums. For centuries the fabulous gems in the shrine of the Three Holy Kings in the cathedral in Cologne Germany were thought to be emeralds, but they are actually peridot.
Peridot is found in lava flows and in once molten rock brought to the surface through volcanic eruption and the cooled in mountainous areas. It is also brought to earth from meteorites. Peridot crystals are also found in the Mogok district of Burma, Norway, Brazil, China, Kenya, Sri Lanka, Australia, and Mexico. In the United States, small stones can be found in the San Carlos Indian Reservation in Arizona.
Peridot is among the oldest known gemstones Ancient Egyptians, around 1580 B.C. to 1350 B.C., created beads from peridot. For Greeks and Romans, peridot was in popular use as intaglios, rings, inlays, and pendants.
The peridot was regarded since ancient times as the symbol of the sun. The Greeks believed that it brought royal dignity upon its wearer. During the Middle Ages, peridot was pierced, then strung on the hair of an ass and attached to the left arm to ward off evil spirits. The Crusaders thought that peridots were emeralds, and brought them back to Europe where they were featured as ornaments in churches.
Peridots were a prized gem late in the Ottoman Empire. The gold throne in Istanbul’s Topkapi museum is decorated with 955 peridot cabochons. Peridots used as turban ornaments and on jeweled boxes. The largest peridot is believed to be a 310 carat gem that belongs to the Smithsonian. A 192 carat peridot of fine clear olive-green is part of the Russian crown jewels, in the Kremlin.