August boasts not one, but three recognized birthstones: peridot, spinel, and sardonyx. Each gem carries a unique history, geological origin, and set of characteristics, offering a diverse range of options for those born in the eighth month of the year. While peridot and spinel represent modern choices, sardonyx holds the distinction as the traditional August birthstone, with a lineage stretching back millennia. This article will explore the origins, properties, and significance of each of these fascinating gemstones, drawing upon available historical and gemological data.
History and Lore
The concept of associating gemstones with specific birth months is a relatively recent development, evolving from ancient beliefs linking gems to the zodiac and the twelve tribes of Israel. Early associations, dating back to the 1st and 5th centuries CE, suggested that each stone offered wearers special powers during its corresponding astrological period. The practice of wearing all twelve gems throughout the year for therapeutic benefits was also common. The modern practice of assigning a single gem to each month emerged between the 16th and 18th centuries, with the National Association of Jewelers formalizing a “modern birthstone” list in 1912.
Sardonyx, as the original August birthstone, possesses the longest documented history. Its use dates back over 4,000 years, notably favored by the Romans for seals and signet rings due to its smooth surface and the property of not sticking to hot wax. Throughout history, the banded colors of sardonyx have made it a popular material for carving cameos and intaglios.
Peridot’s history is equally rich, with origins tracing back to ancient Egypt. The island of Zabargad, now known as Topazios, was a significant source, mined as early as 340–279 BCE. Despite the harsh conditions of the island – earning it names like “Island of Death” – peridot from this location was highly prized and remains sought after today. It was often mistaken for emeralds, even adorning the Shrine of the Three Holy Kings in Germany’s Cologne Cathedral. Some historians speculate that Cleopatra’s famed emerald collection may have actually consisted largely of peridot. The gem was valued for its protective qualities, believed to ward off evil spirits and nightmares.
Spinel’s history is somewhat different, as it was frequently misidentified as ruby for centuries. This led to some of history’s most famous “rubies” actually being spinel, including the approximately 170-carat Black Prince’s “ruby,” now set in the British Imperial State Crown. It wasn’t until the 18th century that spinel was definitively distinguished from ruby based on chemical differences. Red spinel was traditionally believed to be a remedy for blood loss and inflammatory diseases, promoting harmony and easing anger.
Geological Formation and Sources
Each of these August birthstones originates through distinct geological processes and is found in various locations worldwide.
Peridot, a gem variety of the mineral olivine, is often formed under extreme conditions. It can be found in hardened lava, carried from deep within the Earth’s mantle, and remarkably, even within meteorites. While much of the peridot available today comes from China, Myanmar, Pakistan, Tanzania, Vietnam, and the United States, notable historical sources include the Egyptian island of Zabargad. Arizona is the primary source within the United States, with crystals found in volcanic lava flows on the San Carlos Apache Indian Reservation. Myanmar’s Kyaukpon region also yields high-quality peridot with deep color and transparency.
Spinel forms in metamorphic rocks and alluvial deposits. Major sources include Tajikistan, Myanmar, Sri Lanka, Vietnam, Tanzania, and Pakistan. Spinel from Myanmar is particularly renowned for its vibrant pink and red hues.
Sardonyx, a combination of sard and onyx, is a variety of cryptocrystalline quartz (chalcedony). It forms through the layering of brownish-red to brown sard and white or black onyx bands. Specific geological formations and mining locations for sardonyx are not detailed in the provided sources.
Gemological Properties
The three August birthstones exhibit distinct gemological properties.
Peridot: This gem is the yellowish-green to greenish-yellow variety of olivine. Its hardness ranges from 6.5 to 7 on the Mohs scale, making it relatively soft and susceptible to damage from hard wear. It is vulnerable to thermal shock and should not be cleaned with steam or ultrasonic cleaners.
Spinel: Spinel comes in a wide array of colors, including intense red, vibrant pink, orange, purple, violet, blue, and bluish-green. It boasts a hardness of 8 on the Mohs scale, making it a durable gem suitable for various jewelry applications. It is stable when exposed to light and chemicals, though high heat can cause some colors to fade.
Sardonyx: This gem is a banded chalcedony, composed of layers of sard (brownish-red) and onyx (white or black). Its hardness is not explicitly stated in the provided sources, but as a form of chalcedony, it generally falls between 6.5 and 7 on the Mohs scale.
The following table summarizes key properties:
| Gemstone | Chemical Composition | Color | Hardness (Mohs) | Notable Characteristics |
|---|---|---|---|---|
| Peridot | Olivine | Yellowish-green to greenish-yellow | 6.5 - 7 | Formed in lava and meteorites, vulnerable to thermal shock |
| Spinel | Magnesium Aluminum Oxide | Red, Pink, Orange, Purple, Blue, Green | 8 | Durable, stable, historically mistaken for ruby |
| Sardonyx | Cryptocrystalline Quartz (Chalcedony) | Banded Brownish-Red & White/Black | 6.5-7 (estimated) | Used for seals and carvings, smooth surface |
Symbolism and Metaphysical Beliefs
Throughout history, each of these August birthstones has been attributed with various symbolic meanings and metaphysical properties.
Peridot was traditionally believed to symbolize strength and protect against nightmares, evil, and enchantments. Ancient Hawaiians associated it with the tears of the goddess Pele, brought to the surface by volcanoes.
Red spinel, along with other red gems, was thought to be a remedy for blood loss and inflammatory diseases, promoting harmony and easing anger.
Sardonyx, due to its layered structure, has historically been associated with strength, courage, and protection. Its smooth surface made it ideal for seals, symbolizing authority and protection.
Care and Cleaning
Proper care is essential to maintain the beauty of these August birthstones. Peridot, being relatively soft, is not recommended for daily wear in rings and should be protected from scratches. Cleaning should be done with a soft-bristle brush and mild soapy water, avoiding steam or ultrasonic cleaners. Spinel, with its higher hardness, is more durable and can withstand ultrasonic and steam cleaning, though caution should be exercised if the stone contains fractures. The sources do not provide specific cleaning instructions for sardonyx, but gentle cleaning with warm, soapy water is generally recommended for chalcedony.
Conclusion
August’s birthstones – peridot, spinel, and sardonyx – represent a rich tapestry of history, geological wonder, and symbolic meaning. From the ancient origins of sardonyx to the extraterrestrial journey of peridot and the long-misidentified beauty of spinel, each gem offers a unique connection to the past and a captivating allure for the present. Whether chosen for their aesthetic appeal, historical significance, or perceived metaphysical properties, these August birthstones continue to be cherished by gem enthusiasts and jewelry lovers alike.