Birthstones by the Month
The August Birthstone is Peridot
Peridot Mineral Form
The gem-quality variety of olivine is called peridot and occurs in silica-poor igneous rocks such as basalts. This green gem is specifically a magnesium-rich silicate. Peridot receives its unmistakable green color from the presence of iron. Peridot is found in low-quality brownish green and yellows as well.
Peridot has been mined and used in jewelry since antiquity, such as Egyptian jewelry. It is suspected, however, Egyptians and a number of other cultures believed the Peridot stone to be light, yet still richly colored emeralds.
Peridot the August Birthstone
A sharp olivine crystal from the old classic locality for gem peridot. Literally the oldest locality, perhaps dating back to the time of Cleopatra and the Egyptian Empires. [2]
Peridot Facts
During the middle ages it was common for European emissaries to return from travels with large amounts of Peridot. These stones were then used to adorn churches, robes and other religious artifacts. Peridot gems are commonly found in rocks formed by volcanos, but have also been known to travel by pallasites. Pallasites are gem-carrying meteorites and the Peridot found in these is typically referred to as moldavite. The first documented discover of Peridot dates back 4000 years on St. John’s Island. Common places Peridot has been mined include Arizona in the USA, Burma, Sri Lanka and China though a mine of immensely high-quality Peridot was discovered in Pakistan in the 1990s.
Peridot Crystal (Ludwigite, Olivine)
A sharp well formed transparent, lustrous, lime-green, peridot crystal has included sprays of acicular, black, ludwigite, a rare magnesium iron borate. [3]
The characteristics of Peridot
Aside from being known as the August birthstone, Peridot is also a typical gift for the celebration of the 16th year of marriage. This gemstone is on the less-rare side of gem-quality stones, therefore making it a superb choice for more reasonably price jewelry applications. Peridot has a decent Mohs hardness at 6-1/2 to 7, though it is still possible to cause internal fractures or scratch the surface. To properly clean Peridot, it is best to use warm, soapy water. Ultrasonic cleaners and steam cleaners can damage the stone’s integrity or the possible treatment methods. It’s best to avoid dramatic temperature changes as this can compromise the internal integrity of Peridot.
Peridot (Forsterite)
A gem peridot crystal from the classic location for gem forsterite, St. Johns Island in the Red Sea off Egypt. [4]
Cut and Clarity for the August birthstone
Peridot can be tricky to cut, as the stone may crack due to internal tension. This gem is typically cut in faceted step or table cuts as well as rounds and ovals. Cabochons are also not uncommon if the clarity is poor, giving the gem a silky shine. Peridot can be found in many other classical or less-classical shapes, depending on the original size and clarity of the rough.
The value of Peridot
The price of Peridot varies greatly depending on quality of color and size. Darker colors tend to be more expensive than lighter variations though Peridot is still considered an affordable gemstone for the most part. Darker Peridot has less iron while light Peridot is typically high in iron content. In fact, an iron percentage less than 15% produces some of the best coloring. Peridot typically has a high amount of inclusions as is obvious by the original French word for the gem peritôt, meaning unclear.
Forsterite (Peridot)
Crystal of Peridot with excellent color and habit. The faces attractively vary from clear and lustrous to frosted.[5]
Is Peridot ever treated?
Typically, Peridot does not require treatments or enhancements and it is common to find natural Peridot in most jewelry applications. When the stability of the gemstone needs improved, Peridot has been reported to be metal-foiled. Pale stones have also been known to be coated for an enhanced color result. Other potential treatments include colorless oils, wax, and resins (both natural and synthetic) at times if the surface appearance or luster needs improvement.
More about Peridot the August birthstone
According to metaphysical beliefs, Peridot is said to be a stone of compassion, one that brings good health, restful sleep and peace. The stone is staid to balance emotions and thoughts to improve relationships. Peridot has also been said to inspire creativity and good cheer with its bright characteristics.
The American Gem Society's August Birthstone page has more information to help you buy from knowledgeable and skilled jewelers and to help you make the most informed buying decision.
Image Attribution
- By Parent Géry (Own work) [Public domain] via Wikimedia Commons
- Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC BY-SA 3.0], via Wikimedia Commons
- Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC BY-SA 3.0], via Wikimedia Commons
- Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC BY-SA 3.0], via Wikimedia Commons
- Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC BY-SA 3.0], via Wikimedia Commons