For those born in August, a trio of gemstones – peridot, spinel, and sardonyx – claim the honor of birthstone status. However, it is peridot that enjoys the most widespread recognition and a particularly fascinating history. Often called the “evening emerald” due to its vibrant green hue and capacity to sparkle even in low light, peridot is a gemstone with origins both terrestrial and extraterrestrial, steeped in ancient lore and modern appeal. This article will delve into the geological formation, historical significance, gemological properties, and symbolism of peridot, offering a comprehensive overview of this captivating August birthstone.
A History Shrouded in Misidentification
The story of peridot is, in many ways, a story of mistaken identity. Throughout history, this gem has frequently been confused with other green stones, most notably emerald and topaz. The island of Topazios in the Red Sea, now known as Zabargad, was believed to be a source of topaz, but in reality, yielded significant quantities of peridot. Ancient scholars, including Pliny the Elder, often referred to peridot as “topaz,” contributing to this long-standing misnomer.
Some historians even speculate that the famed emeralds of Cleopatra’s collection were, in fact, peridot. The gem’s presence in the Shrine of the Three Holy Kings in Germany’s Cologne Cathedral, initially believed to be emeralds, further illustrates this historical confusion. The earliest documented use of peridot dates back over 4,000 years, with evidence of its use in ancient Egyptian jewelry. It was highly valued and often set in gold.
While sardonyx holds the distinction of being the original August birthstone, and spinel was added more recently in 2016, peridot’s enduring appeal and rich history have solidified its position as the most popular choice for those celebrating an August birthday. The addition of spinel to the list of August birthstones was a relatively recent change, occurring when the Jewelers of America and the American Gem Trade Association updated their birthstone list in 2016.
Geological Origins: From Mantle to Meteorite
Peridot’s formation is as unique as its history. Unlike many gemstones formed in the Earth’s crust, peridot originates deep within the Earth’s mantle, specifically in the olivine mineral group. It is brought to the surface through volcanic activity, found within hardened lava flows. This explains its association with extreme conditions, as noted in several sources.
Remarkably, peridot has also been discovered in pallasite meteorites – stony-iron meteorites that formed in the asteroid belt. While these meteoritic peridots are typically too small for use in jewelry, their existence adds to the gem’s mystique and reinforces its connection to the cosmos. Larger, gem-quality peridot is primarily sourced from the Earth’s upper mantle, carried to the surface by volcanic eruptions.
Gemological Properties: A Distinctive Green
Peridot’s chemical formula is (Mg,Fe)2SiO4, indicating it is composed primarily of magnesium and iron silicates. The amount of iron present within the crystal structure is responsible for peridot’s characteristic green color, ranging from yellowish-green to greenish-yellow. The intensity of the color depends on the iron content; higher iron levels result in a richer, more vibrant green.
While often compared to emerald, peridot possesses distinct gemological properties that set it apart. It has a hardness of 6.5 to 7 on the Mohs scale, making it moderately durable and suitable for most jewelry applications. However, it is softer than emerald (hardness of 7.5-8), making it more susceptible to scratches and abrasion.
Peridot exhibits a vitreous luster and a distinctive double refraction, a property that can be observed by jewelers when examining the stone. Its refractive index is between 1.654 and 1.689. Peridot typically occurs in small sizes, with larger stones being relatively rare and valuable.
| Property | Value |
|---|---|
| Chemical Formula | (Mg,Fe)2SiO4 |
| Hardness (Mohs) | 6.5 - 7 |
| Luster | Vitreous |
| Refractive Index | 1.654 - 1.689 |
| Crystal System | Orthorhombic |
Symbolism and Metaphysical Beliefs
Throughout history, peridot has been attributed with various symbolic meanings and metaphysical properties. Ancient Egyptians believed peridot possessed healing powers and protected against nightmares. It was often used in amulets and talismans. In some cultures, peridot was thought to bring good health, restful sleep, and peace of mind.
The gem is often associated with prosperity, good fortune, and positive energy. Some modern interpretations suggest peridot can help release negative emotions, promote clarity of thought, and enhance creativity. While these beliefs are not scientifically substantiated, they contribute to the gem’s enduring appeal and cultural significance.
Care and Cleaning
Due to its moderate hardness, peridot requires careful handling and cleaning. It is susceptible to scratches from harder materials and can be damaged by harsh chemicals or ultrasonic cleaners. The recommended cleaning method involves using warm, soapy water and a soft brush. Avoid steam cleaning or abrasive cleaners, as these can damage the stone’s surface. Regular cleaning will help maintain peridot’s brilliance and luster. It is also advisable to remove peridot jewelry before engaging in strenuous activities to prevent damage.
Conclusion
Peridot, the captivating August birthstone, offers a unique blend of historical intrigue, geological wonder, and aesthetic beauty. From its ancient origins and frequent misidentification to its formation in the Earth’s mantle and even within meteorites, peridot’s story is one of remarkable resilience and enduring appeal. Its vibrant green hue, coupled with its symbolic associations with prosperity and good health, makes it a cherished gemstone for those born in August and a captivating addition to any jewelry collection. The gem’s enduring popularity and fascinating history ensure its continued significance in the world of gemstones.