August, the eighth month of the year, is named after Augustus Caesar, the first Emperor of Rome. In honor of its namesake, the month of August is associated with three distinct gemstones: peridot, sardonyx, and spinel. Each of these stones carries a unique history, a range of physical and symbolic properties, and a special place in the tradition of birthstones. This article delves into the characteristics, origins, symbolism, and care of the August birthstones, offering a comprehensive overview of their significance in gemology and culture.
Introduction
The August birthstones—peridot, sardonyx, and spinel—are each remarkable in their own right. Peridot, with its vibrant green hue, is the most widely recognized of the three and has a long history of use in jewelry and ornamentation. Sardonyx, a banded chalcedony, is one of the oldest known birthstones, with roots in ancient civilizations. Spinel, a more recent addition to the August lineup, is prized for its brilliance and similarity to ruby and sapphire. Together, these three stones reflect the rich tapestry of gemstone tradition and the evolving tastes of the jewelry industry.
This article explores the historical and cultural significance of each August birthstone, their geological properties, and their symbolic meanings. It also addresses practical aspects such as care and maintenance. Drawing from authoritative and historical sources, this piece aims to provide a thorough understanding of these gems for gemstone enthusiasts, jewelry buyers, and students of gemology.
History and Lore
The tradition of associating gemstones with specific months dates back to the first century, but the modern system of birthstones was standardized in 1912 by the American National Association of Jewelers (now the Jewelers of America). Peridot was designated as the August birthstone at that time, a decision influenced by its natural formation in volcanic environments. August is one of the warmest months in the northern hemisphere, and peridot’s connection to lava flows and its vivid green color made it a fitting symbol for the month.
Sardonyx, on the other hand, has a much older history. It is the oldest of the three August birthstones, with a documented use in ancient Egypt, Greece, and Rome. The gem is composed of two varieties of chalcedony: sard, which is a reddish-brown to orange color, and onyx, which is typically white or black. This banded appearance made sardonyx ideal for cameos, seals, and amulets. Ancient Roman soldiers believed sardonyx brought good luck and protection, and it was often used in signet rings for engraving wax seals.
Spinel was added to the August birthstone list in 2016, recognizing the gem’s beauty and versatility. Spinel, which can mimic the appearance of ruby and sapphire, was often mistaken for these stones in the past. Red spinel, in particular, was frequently misidentified as ruby, leading to some historically significant pieces being later reclassified. The inclusion of spinel in the August birthstone lineup reflects the growing appreciation for this gemstone and its value as an alternative to more expensive stones.
Geological Formation and Sources
Each of the August birthstones has a unique geological origin and is found in various parts of the world.
Peridot
Peridot is a variety of the mineral olivine, and it forms under extreme conditions deep within the Earth’s mantle. It is brought to the surface through volcanic activity or by meteorites. Peridot can be found in hardened lava and in meteorites, which is a rare and fascinating aspect of its formation. The presence of iron in its chemical composition gives peridot its distinctive yellow-green to greenish-yellow color. High-quality peridot is often found in the United States (particularly in Arizona), as well as in Myanmar, China, and Saudi Arabia.
Sardonyx
Sardonyx is a banded chalcedony composed of sard and onyx. Chalcedony is a microcrystalline form of quartz, and sardonyx forms in sedimentary and volcanic environments. The reddish-brown sard layer is due to the presence of iron, while the white or black onyx layer is composed of pure quartz. Sardonyx is mined in several regions, including India, Brazil, and the United States. It has been used for thousands of years in jewelry and decorative objects, with historical deposits found in ancient Egypt and Rome.
Spinel
Spinel is a mineral composed of magnesium aluminum oxide and is found in igneous and metamorphic rocks. It forms in magmatic environments and is often found in association with corundum (the mineral that includes ruby and sapphire). Spinel is found in various parts of the world, including Myanmar, Sri Lanka, Afghanistan, and Tanzania. The gem is known for its brilliance and range of colors, from deep red to vibrant blue and even pink and orange. The most valuable spinel stones are those with intense color and clarity.
Gemological Properties
Understanding the gemological properties of each August birthstone is essential for both collectors and jewelers. These properties include hardness, color, clarity, and refractive index, which affect the gem’s durability and appearance.
Peridot
- Hardness: Peridot ranks 6.5 to 7 on the Mohs scale, which means it is relatively durable but still susceptible to scratches and chips.
- Color: Peridot is known for its yellow-green to greenish-yellow color, which is caused by the presence of iron in its chemical composition.
- Clarity: Peridot is typically transparent to translucent and often contains inclusions, which are natural features that can add character to the stone.
- Refractive Index: The refractive index of peridot ranges from 1.65 to 1.70, giving it a moderate level of brilliance.
- Chemical Composition: Peridot is a silicate mineral with the chemical formula (Mg, Fe)₂SiO₄.
Sardonyx
- Hardness: Sardonyx has a hardness of 6.5 to 7 on the Mohs scale, making it suitable for everyday wear, especially in rings and pendants.
- Color: Sardonyx displays a combination of sard (reddish-brown to orange) and onyx (white or black) in distinct bands. The sard layer is due to iron, while the onyx is pure quartz.
- Clarity: Sardonyx is typically translucent and often contains inclusions, which are characteristic of chalcedony.
- Refractive Index: The refractive index of sardonyx is around 1.53 to 1.54, which is typical for chalcedony.
- Chemical Composition: Sardonyx is a form of chalcedony, which is a microcrystalline form of quartz (SiO₂).
Spinel
- Hardness: Spinel has a hardness of 8 on the Mohs scale, making it a durable gemstone that is suitable for all types of jewelry.
- Color: Spinel comes in a wide range of colors, including red, blue, pink, orange, and black. The most valuable spinel stones are those with intense red or blue hues.
- Clarity: Spinel is typically transparent and often has high clarity, with few inclusions. High-quality spinel can rival the clarity of ruby and sapphire.
- Refractive Index: The refractive index of spinel is around 1.718 to 1.722, which gives it a high level of brilliance.
- Chemical Composition: Spinel is composed of magnesium aluminum oxide (MgAl₂O₄).
Symbolism and Metaphysical Beliefs
The August birthstones are not only valued for their beauty and rarity but also for their symbolic and metaphysical significance. These beliefs have evolved over centuries and vary across cultures.
Peridot
Peridot has been associated with positive energy, prosperity, and protection. In ancient times, it was believed to ward off nightmares and promote restful sleep. The gemstone is also associated with abundance and is often used to attract wealth and good fortune. Peridot is considered a stone of light and is believed to inspire clear thinking and promote a sense of peace and calm.
Sardonyx
Sardonyx has long been associated with strength, courage, and protection. Ancient Romans used sardonyx as an amulet for victory in battle and for enhancing communication skills. The gemstone is also believed to promote open communication and healthy relationships. In modern metaphysical practices, sardonyx is used to enhance confidence and to support spiritual growth.
Spinel
Spinel is associated with vitality, passion, and emotional balance. The gemstone is believed to stimulate the heart and promote emotional well-being. Spinel is also associated with courage and is thought to help individuals face challenges with confidence. In some cultures, spinel is considered a stone of love and is used to enhance romantic relationships.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of August birthstone jewelry. Each gemstone has specific care requirements based on its hardness and sensitivity to heat and chemicals.
Peridot
Peridot should be cleaned with warm, soapy water and a soft cloth. It is sensitive to heat and should not be exposed to high temperatures. Peridot should be stored separately from harder gemstones to prevent scratches. Avoid using ultrasonic cleaners or steam cleaners, as they can damage the stone.
Sardonyx
Sardonyx can be cleaned with warm, soapy water and a soft cloth. It is relatively durable but should be kept away from harsh chemicals. Sardonyx should be stored in a dry place to prevent moisture damage. Avoid exposing sardonyx to extreme heat or sudden temperature changes, as this can cause cracking.
Spinel
Spinel is a durable gemstone that can be cleaned with warm, soapy water and a soft cloth. It is resistant to heat and can be cleaned with ultrasonic or steam cleaners. Spinel should be stored in a secure place to prevent scratches from harder gemstones. It is also resistant to most chemicals, making it easy to care for.
Conclusion
The August birthstones—peridot, sardonyx, and spinel—each offer a unique combination of beauty, history, and symbolism. Peridot, with its vibrant green color and connection to volcanic activity, is a fitting symbol for the month of August. Sardonyx, with its banded appearance and ancient roots, has been cherished for thousands of years. Spinel, a more recent addition to the August lineup, brings a new dimension to the tradition of birthstones with its brilliance and versatility.
These gemstones are not only valuable for their aesthetic appeal but also for the rich traditions and meanings they carry. Whether worn for personal significance, as a symbol of good fortune, or as a piece of fine jewelry, the August birthstones continue to captivate and inspire.