Peridot is the gem variety of the mineral Olivine. Peridot is the birthstone for August and used as the anniversary gemstone for the 16th year.
The origin of the name Peridot is unclear, but it has long been associated with the sun, the Egyptians called it the “gem of the sun”, due these associations it is believed to drive out darkness, whether that be nightmares or demons and evil spirits, it is also been believed to help with ailments in digestion and the liver and kidneys.
Peridot is known to occur deep in the earth and is frequently associated with Diamonds when it is mined. Peridot also comes from outer space, being frequently contained in meteorites, many of the stones big enough to facet as gemstones.
Peridot is what is classed as an idiochromatic gemstone, meaning self-coloured, the iron that causes the colour is an essential component in its chemical makeup. This gives Peridot a very narrow colour range, from yellowish green to brownish green with the most desirable colour being a vibrant grass green. Due to the vibrancy and uniqueness of the colour of Peridot it often is worn by confident people with a well-defined personal sense of style.
Peridot are assessed for quality in much the same way as many coloured stones, faceted gems used in jewellery are frequently free from inclusions that can be seen with the naked eye, with lower clarity stones usually used for beads and cabochons. Peridot can occur in larger sizes with gems as big as 50ct being cut, but in recent years it has become more difficult to find the higher grade material used for fine Peridot in these larger sizes.
Peridot can be an affordable gem, not commanding the high ct prices of other gemstones, a dazzling suite of jewellery can be made using Peridot. Prices range from a few pounds per ct for smaller, commercial quality stones to a few thousand per ct for very fine material in larger sizes. Peridot does require a little more care than some stones, being relatively soft and susceptible to attack from some chemicals and can be damaged by thermal shock. Care must be taken not to scratch the stone when wearing, and it should only be cleaned with warm soapy water and a soft cloth.
Peridot is rarely treated, so a good choice if you are looking for a natural stone, some very heavily included material can be oiled or impregnated in some way, but this is uncommon.