Peridot, a vibrant gem displaying shades of olive green to greenish yellow, holds a prominent place as one of the recognized birthstones for August. Its history is rich with misidentification – often mistaken for emeralds throughout much of recorded history – and steeped in lore, from being called the “gem of the sun” by the Egyptians to being referred to as the “evening emerald” by the Romans. Beyond its aesthetic appeal, peridot possesses unique gemological properties and a fascinating origin story, sometimes even originating from beyond our planet. This article will delve into the history, geological formation, properties, symbolism, and care of this captivating gemstone.
History and Lore
The story of peridot is one of enduring fascination and occasional confusion. Ancient Egyptians revered peridot, referring to it as the “gem of the sun,” and adorned themselves with it in elaborate jewelry. A compelling theory suggests that Cleopatra’s famed emerald collection was, in fact, largely composed of peridot. This misidentification continued for centuries, as evidenced by the 200-carat gemstones decorating the Shrine of the Three Holy Kings in Germany’s Cologne Cathedral, long believed to be emeralds but now confirmed as peridot.
The Romans, too, held peridot in high regard, calling it the “evening emerald” due to its ability to maintain its vibrant color even in low light conditions. Throughout history, peridot has been associated with prosperity, growth, and openness, believed to strengthen life and bring positive energy to the wearer. It is also the traditional gift given to celebrate a 15th wedding anniversary.
Geological Formation and Sources
Peridot is a variety of the mineral olivine, formed under extreme conditions. It is often found in hardened lava, carried from deep within the Earth’s mantle. Remarkably, peridot has even been discovered in pallasite meteorites, estimated to be between 4 and 5 billion years old, dating back to the origins of our solar system. In 2005, peridot was identified in comet dust retrieved by the Stardust robotic space probe, further cementing its extraterrestrial connection.
While historically sourced from the Red Sea island of Topazios (which ironically gave its name to topaz, another gemstone), modern peridot sources include Tanzania, where a 2007 discovery yielded stones in pinkish and orangy red hues, as well as purple and blue varieties. Other notable sources include Brazil, Germany, Czechoslovakia, Madagascar, and the United States.
Gemological Properties
Peridot’s distinctive olive-green color is a result of its chemical composition, primarily iron magnesium silicate. It is not as light-dependent as blue or red gemstones, maintaining its color consistently in various lighting conditions. A unique optical property of peridot is its extremely high double refraction; when viewed closely through the gemstone, two of each pavilion facet can be observed.
Peridot registers an 8 on the Mohs scale of hardness, making it a relatively durable gem suitable for rings and other jewelry. However, the presence of fractures within the stone can pose a problem, requiring careful handling. It is stable when exposed to light and chemicals, but high heat can cause some colors to fade.
Here's a summary of key gemological properties:
| Property | Description |
|---|---|
| Mineral | Olivine |
| Chemical Formula | (Mg, Fe)₂SiO₄ |
| Color | Yellowish green to greenish yellow |
| Hardness (Mohs) | 8 |
| Refraction | High double refraction |
| Origin | Mantle, meteorites, volcanic activity |
Symbolism and Metaphysical Beliefs
Throughout history, peridot has been imbued with symbolic meaning. Ancient beliefs associated it with protection, particularly for Roman soldiers who wore rings carved with the image of Mars, believing it would shield them in battle. Today, peridot is linked to courage, happiness, and clear communication, and is thought to bring stability to marriages and partnerships. It is also believed to increase prosperity and growth.
In ancient times, sardonyx, another August birthstone, held significant spiritual weight, appearing in the High Priest’s breastplate as described in the Old Testament, representing the strength of spiritual life.
Care and Cleaning
Due to its hardness of 6.5 to 7 on the Mohs scale, sardonyx requires careful handling, especially when worn as a ring. Peridot, being slightly harder at 8, is more durable but still benefits from gentle care. Both gemstones can be cleaned using warm soapy water and a soft-bristle brush.
Ultrasonic and steam cleaners can be used for peridot and spinel, but caution is advised, particularly if the stones contain fractures. Sardonyx, like other forms of chalcedony, is sometimes dyed, and high heat during jewelry repair could affect the color. It is always safest to opt for warm soapy water for cleaning these gemstones.
Spinel: A Rising Star
While peridot and sardonyx have long histories, spinel is a more recently appreciated August birthstone. For centuries, red spinel was often mistaken for ruby, a more highly valued gem. However, with increasing consumer awareness and appreciation for its unique qualities, spinel has emerged as a desirable gemstone in its own right. A 2007 discovery in Tanzania revealed spinel in a range of colors, including pinkish, orangy red, purple, and blue hues, further enhancing its appeal. Spinel is also relatively durable, registering an 8 on the Mohs scale, making it suitable for everyday wear.
Modern Applications and Jewelry
Today, peridot, spinel, and sardonyx are all popular choices for jewelry, particularly rings. Peridot rings are often crafted in sterling silver or gold, showcasing the gem’s vibrant green color. Spinel’s range of colors allows for greater versatility in design, while sardonyx’s banded patterns are often utilized in cameos and intaglios. Rings featuring these birthstones are available in a variety of styles, from classic and elegant designs to more contemporary and unique pieces. Many jewelers offer custom design services, allowing customers to create personalized rings tailored to their preferences. Rings are often made with platinum-coated sterling silver to enhance durability and brilliance.
Conclusion
Peridot, spinel, and sardonyx represent a diverse and fascinating trio of August birthstones. From the ancient lore surrounding peridot’s origins as the “gem of the sun” to the recent appreciation of spinel’s unique beauty and the historical significance of sardonyx, these gemstones offer a rich tapestry of history, science, and symbolism. Whether chosen for their aesthetic appeal, their metaphysical properties, or their personal significance, these August birthstones continue to captivate and inspire.