Peridot

Peridot is a gem-quality variety of the mineral olivine. It belongs to the forsterite-fayalite mineral series. Some even refer to peridot as ‘olivine’, but when it comes to the gemstone, ‘peridot’ is the correct term. Peridot is an idiochromatic gem, meaning its color comes from the basic chemical composition of the mineral itself and not from minor traces of impurities. Thus, peridot is found only in green. In fact, peridot is one of the few gemstones available that can be found only in one color, although the shades of green may vary from light yellowish to dark brownish-green.

The name ‘peridot’ was derived from the Arabic word for gem – ‘faridat’. It is sometimes referred to as ‘chrysolite’, a word derived from the Greek word ‘goldstone’. It is one of the oldest known gemstones, with records dating back as early as 1500 B.C. Historically, the volcanic island of Zabargad (St. John) in the Red Sea, east of Egypt, had the most important deposit that was exploited for over 3500 years. Today, the finest quality peridot comes from Mogok in Burma, although Pakistani peridot is now highly regarded as well. There are other very important deposits found in Arizona, China and Vietnam. Peridot has also been discovered in fallen meteors and it has also been discovered on Mars and the moon in olivine form.

Peridot Color

Peridot is one of the few gemstones that comes in a single color. The depth of green depends on its level of iron content. Peridot’s color can vary from yellow-green and olive to brownish green and looks best under natural daylight. Its vivid green color does not change under artificial light. The best-colored peridot has an iron percentage of less than 15% and typically includes some trace elements of nickel and chromium, which contribute to its color. A deep and intense green colored peridot is considered the most desirable and the most valuable.

Peridot Clarity and Luster

Peridot occurs with excellent transparency. Eye-clean specimens are abundant. Larger stones may appear slightly cloudy owing to the presence of inclusions and impurities. When cut and polished, peridot has an attractive, greasy and vitreous luster.

Peridot Cut and Shape

Peridot is typically faceted due to its excellent transparency. Table and step cuts are very popular, as well as unconventional checkerboards. Peridot can be found in many shapes including fancies and traditional rounds, ovals, emeralds (octagons) and cushions.

Peridot Origins and Sources

Most gemstones are formed in earth’s crust, but peridot is formed much deeper in the mantle region. Peridot crystals form in magma from the upper mantle and are brought to the surface by tectonic or volcanic activity where they are found in extrusive igneous rocks. Historically the volcanic island Zabargad (St. John) in the Red Sea was the location of the most important deposit. It was exploited for 3500 years before it was abandoned for many centuries; later, it was rediscovered around 1900 and has been heavily exploited ever since.

Today, the most important deposits are found in Pakistan (in the Kashmir region and the Pakistan-Afghanistan border region). Beautiful material is also found in upper Myanmar (Burma) and Vietnam. Other deposits are found in Australia (Queensland), Brazil (Minas Gerais), China, Kenya, Mexico, Norway (north of Bergen), South Africa, Sri Lanka, Tanzania and the United States (Arizona and Hawaii).

Peridot Mythology

Peridot has an ancient history and has been used for jewelry for thousands of years. It is a gemstone with a fascinating history, both in nature and culture. The ancient Romans called it ‘evening emerald’ since its color did not darken at night, but could still be appreciated by candlelight and the light of a campfire. It is a gem especially connected with ancient Egypt, and some historians believe that the famous emeralds of Cleopatra were actually peridot gems. Peridot was also brought back to Europe by the Crusaders and was often used to decorate medieval churches.

Peridot is mentioned in the Bible under the Hebrew name of ‘pitdah’. Peridot gems along with other gems were probably used in the fabled breastplates of the Jewish high priests, artifacts that have never been found. Legend has it that peridot was the favorite gemstone of Cleopatra. Crusaders brought peridot to Central Europe where it was found in many medieval churches such as the Cologne Cathedral. In the Baroque era, peridot experienced another short period of popularity, before it was forgotten again. Napoleon used peridot to assure Josephine of his undying love and admiration, which of course happened before he had their marriage annulled.

Source: Gem Select