For those born in the eighth month of the year, the choice of a birthstone is not a simple one. August is uniquely endowed with three official birthstones: the radiant green of peridot, the dazzling versatility of spinel, and the historic banding of sardonyx. This trio offers a remarkable spectrum of color, lore, and geological origin, reflecting the diverse and vibrant energy of late summer. While sardonyx holds the distinction of being the original and most ancient birthstone for August, the later additions of peridot and spinel were made to provide consumers with more options for color, affordability, and availability. Together, these three gems tell a story of ancient beliefs, geological marvels, and modern appreciation, making August one of the most celebrated months in the world of gemstones.
This article will explore each of these three remarkable gems in detail. We will begin with the "gem of the sun," peridot, delving into its unique formation and its long history of being mistaken for other precious stones. Next, we will uncover the story of spinel, a gem that spent centuries in the shadow of the ruby before finally being recognized for its own intrinsic worth. Finally, we will examine sardonyx, the ancient August birthstone, whose banded layers of chalcedony have been carved into seals and amulets for over four millennia. By examining the history, geology, and gemological properties of each, we can fully appreciate the richness that the August birthstone trinity has to offer.
Peridot: The Gem of the Sun
Peridot is perhaps the most well-known of the three August birthstones, celebrated for its distinctive lime-green glow and its unique geological story. It is the yellowish green to greenish yellow gem variety of the mineral olivine. Unlike many gemstones that can be found in a wide array of colors, peridot is notable for appearing in only one color: a distinctive green that can range from a yellowish-green to a deep olive hue. This consistency of color is one of its most defining characteristics.
The history of peridot is long and often muddled with that of other green gems. Throughout history, peridot has frequently been confused with topaz and emerald due to its similar appearance. The Red Sea island of Topazios, a place whose name is a purported source for the gemstone topaz, actually produced peridot. This historical confusion is famously illustrated by the Shrine of the Three Holy Kings in Germany’s Cologne Cathedral. This shrine is decorated with 200 carats of gems that were believed for centuries to be emeralds but are, in fact, peridot. Some historians even speculate that Cleopatra’s famous emerald collection may have actually been comprised of peridot. The word “peridot” itself is believed to derive from the Arabic word faridat, meaning gem.
Ancient cultures held peridot in high regard. The ancient Egyptians prized it immensely, referring to it as the "gem of the sun." They believed it offered protection from the terrors of the night and was a source of health, happiness, and strength. It was often used in jewelry and religious artifacts. The Romans were also great admirers, calling it the "evening emerald" because its vibrant green color remained visible and beautiful even under artificial light. This enduring luminosity has contributed to its lasting appeal.
Peridot’s formation is one of the most extraordinary among all gemstones. It is known for being formed under extreme conditions. While many gems crystallize in the Earth’s crust, peridot can be found in the hardened lava that carried it from deep within the Earth’s mantle. This indicates a volcanic origin, bringing gem-quality olivine from depths of up to 120 miles (200 kilometers) to the surface. Even more remarkably, some peridot has been found in meteorites that traveled from outer space, making it one of the few gems that can be extraterrestrial in origin. This unique formation process underscores the gem's connection to powerful and primordial forces.
Spinel: The Great Impostor
For centuries, spinel was the unsung hero of the gem world, its beauty and value overshadowed by its close resemblance to one of the most prized gems: the ruby. The spinel birthstone was underappreciated until recently, as today’s consumers seek out alternatives to ruby, a gem with which red spinel was mistaken for centuries. This long history of confusion has given spinel a rich, if sometimes misunderstood, past.
The most famous example of this historical mix-up is the Black Prince’s Ruby, a massive 170-carat red spinel that is set in the British Imperial State Crown. For hundreds of years, it was believed to be a ruby. Similarly, the Timur Ruby, a 361-carat red spinel, also carries a name that reflects this long-held error. These historical gems, now recognized as spinel, demonstrate that the finest red spinels possess a vividness and clarity that can rival, and sometimes even surpass, that of ruby.
Spinel is a magnesium aluminium oxide with a hardness of 8 on the Mohs scale, making it a durable and excellent choice for all types of jewelry. While it is most popular in its vivid red variety, which can be mistaken for ruby, spinel actually occurs in a wide range of colors, including pink, orange, blue, or black. The cobalt-blue spinel is particularly rare and highly valued. Its excellent hardness and lack of cleavage (the tendency to break along flat planes) make it a robust gem that is well-suited for everyday wear.
The recent addition of spinel to the official list of August birthstones by the American Gem Trade Association (AGTA) and Jewelers of America (JA) in 2016 was a recognition of its growing popularity and its status as a distinct and valuable gem in its own right. This addition provided consumers with a durable and more affordable alternative to ruby, while also honoring a gem with its own fascinating history. No longer just a "great impostor," spinel is now celebrated for its own unique brilliance and wide color palette.
Sardonyx: The Original August Birthstone
Sardonyx is the original August birthstone, with a documented history that dates back more than 4,000 years. It is a variety of banded chalcedony, which is a microcrystalline form of quartz. Sardonyx is composed of alternating layers of sard (a reddish-brown variety of chalcedony) and onyx (a black and white variety of chalcedony). This banding gives the stone its distinctive appearance, with layers that can be straight, curved, or irregular.
The ancient world held sardonyx in particularly high esteem. It was highly valued in ancient Egypt, Greece, and Rome, where it was used to make seals, amulets, rings, and other adornments. Its hardness of around 7 on the Mohs scale made it ideal for carving, a process known as cameo or intaglio work. The stone’s banded appearance was more than just decorative; it was believed to symbolize strength, protection, and clarity of thought. Roman soldiers would often wear sardonyx rings, believing the stone would protect them in battle and grant them courage.
The name "sardonyx" itself reflects its composition: "sard" from the reddish-brown sard layer and "onyx" from the black onyx layer. The most prized sardonyx stones exhibit a sharp contrast between the bright white onyx and the rich, reddish-brown sard layers. As a member of the chalcedony family, it is a relatively hard and durable gemstone, making it suitable for all kinds of jewelry, including rings, pendants, and bracelets. While its popularity as a birthstone has been supplemented by the addition of peridot and spinel, sardonyx remains a stone of great historical and symbolic importance, connecting the modern wearer to a tradition of adornment that spans millennia.
Gemological Properties at a Glance
To better understand the distinct characteristics of the three August birthstones, it is helpful to compare their key gemological properties. Each stone offers a different profile in terms of hardness, chemical composition, and color, which influences both its use in jewelry and its care requirements.
| Gemstone | Mineral Family | Chemical Formula | Hardness (Mohs Scale) | Typical Colors |
|---|---|---|---|---|
| Peridot | Olivine | (Mg, Fe)₂SiO₄ | 6.5 - 7 | Yellowish-green to olive green |
| Spinel | Spinel | MgAl₂O₄ | 8 | Red, pink, orange, blue, black |
| Sardonyx | Chalcedony (Quartz) | SiO₂ | 7 | Banded reddish-brown and white/black |
As the table illustrates, spinel is the hardest of the three, making it exceptionally durable for jewelry. Peridot, at 6.5 to 7, is also quite suitable for jewelry but requires slightly more care to avoid scratches. Sardonyx, with a hardness of 7, is also durable, especially for a stone that is often carved. The color range is also vastly different, with peridot being consistently green, spinel offering a rainbow of options, and sardonyx providing a unique patterned appearance.
Metaphysical Beliefs and Symbolism
Each of the three August birthstones carries a rich legacy of symbolism and metaphysical beliefs, passed down through various cultures and eras.
Peridot, the "gem of the sun," has long been associated with light, positivity, and protection. The ancient Egyptians believed it could ward off evil spirits and protect its wearer from the terrors of the night. It was also thought to bring health, happiness, and strength. In modern crystal healing, peridot is often associated with abundance, prosperity, and good fortune. Its vibrant green color is said to energize the heart and promote feelings of warmth and openness.
Spinel, though its metaphysical lore is less documented in the provided sources, has gained a reputation in modern times as a stone of revitalization. Its resemblance to ruby has lent it some of the same symbolic associations with passion and energy. As a gem that was long mistaken for a more precious stone, it can also be seen as a symbol of revealing one's true identity and value.
Sardonyx, with its ancient history, is deeply connected to themes of strength, protection, and courage. Its use in Roman seals and amulets was rooted in the belief that it could protect the wearer from harm and grant them stability and clarity of mind. It is often considered a stone of discipline and strong will, helping individuals to maintain self-control and achieve their goals. The banded layers are seen as a symbol of unity and harmony.
Care and Cleaning
Proper care is essential for maintaining the beauty of any gemstone. The different hardness levels and chemical compositions of the three August birthstones require specific considerations.
Peridot (Hardness 6.5-7): While reasonably durable, peridot is softer than spinel and sardonyx. It should be stored carefully to avoid being scratched by harder gems. It can be cleaned using warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaning, as sudden temperature changes can cause fractures.
Spinel (Hardness 8): Spinel is quite durable and relatively easy to care for. It can be cleaned with warm, soapy water and a soft brush. It is generally safe to use an ultrasonic cleaner, but it is always wise to be cautious. Steam cleaning is usually acceptable.
Sardonyx (Hardness 7): As a variety of chalcedony, sardonyx is durable enough for everyday wear. It can be cleaned with warm, soapy water and a soft brush. Ultrasonic cleaners are generally safe, but steam cleaning should be avoided. Care should be taken with carved sardonyx pieces, as the delicate details can be damaged by harsh cleaning methods.
Conclusion
The birthstones of August—peridot, spinel, and sardonyx—offer a compelling narrative of geological wonder, historical depth, and aesthetic diversity. From the sun-drenched origins of peridot, whether in the Earth's mantle or in meteorites from space, to the centuries of mistaken identity that defined spinel's journey, and the ancient, protective power of banded sardonyx, each gem provides a unique connection to the natural world and to human history. Together, they form a trinity that allows those born in August to choose a stone that truly resonates with their personal style and spirit. Whether one is drawn to the vibrant green of the evening emerald, the brilliant fire of the great impostor, or the stoic strength of the ancient seal, the August birthstones are a testament to the enduring allure and rich legacy of the world's most treasured gems.