For those born in August, the gemstone selection is uniquely abundant, offering a trio of distinct treasures: Peridot, Spinel, and Sardonyx. Unlike most months, which are traditionally associated with a single stone, August's birthstone list has evolved over time, reflecting both historical legacy and modern gemological appreciation. This diversity provides a remarkable spectrum of color, origin, and lore, from the sunlit green of volcanic peridot to the deep reds of once-misidentified spinel and the banded bands of ancient sardonyx. Understanding these three gems requires delving into their unique geological journeys, their long histories in human culture, and the specific properties that make each one a worthy choice for jewelry and collection.
The evolution of August's birthstones tells a story of changing tastes and expanding knowledge. Sardonyx stands as the original, a stone with a history stretching back over 4,000 years, deeply embedded in the seals and signet rings of ancient Rome. Peridot was later added, bringing its vibrant, distinctive green to the forefront. Most recently, in 2016, the American Gem Trade Association and Jewelers of America officially added spinel to the list, giving recognition to a gem that had been underappreciated for centuries, often mistaken for ruby. This article will explore the geological formation, historical significance, gemological properties, and care instructions for each of these three August birthstones, providing a comprehensive guide for enthusiasts, collectors, and anyone captivated by the stories held within these Earth-born gems.
The Original Stone: Sardonyx and Its Millennia of History
Sardonyx is the most ancient of the August birthstones, with a history that predates the other two by millennia. It is a variety of chalcedony, which is a cryptocrystalline form of quartz. Specifically, sardonyx is a composite stone, characterized by alternating bands of two different types of chalcedony: sard and onyx. The sard component provides the brownish-red to brown to dark orange layers, while the onyx contributes the typically white or black bands. This banded structure is not merely decorative but is fundamental to the stone's identity and historical use.
The primary appeal of sardonyx in antiquity, particularly in the Roman Empire, was its practical utility. The stone was a popular choice for Roman seals and signet rings because its smooth, waxy surface resisted hot wax, ensuring a clean impression. This functional characteristic made it indispensable for official documents and personal correspondence. Beyond Rome, sardonyx was associated with a range of virtues. In ancient Egypt, where its history can be traced even farther back, this gemstone was linked to courage, happiness, and clear communication. It was also believed to promote stability in marriage and other relationships, a belief that resonated across cultures.
The use of sardonyx extended into the creation of cameos. In Ancient Rome, it was commonly used to carve cameos of Venus, worn on necklaces by women seeking to harness the power of the goddess of love. Men, on the other hand, might wear cameos of Mars, hoping to gain protection in battle from the god of war. This dual association with love and war highlights the stone's perceived power and versatility in ancient symbolism. The stone's name itself is a combination of "sard" and "onyx," directly referencing its two constituent parts. Its durability and distinctive banding have ensured its continued use in jewelry and decorative objects throughout history.
The Vibrant Green of Volcanic and Extraterrestrial Origins: Peridot
Peridot is the yellowish-green to greenish-yellow gem variety of the mineral olivine. It is arguably the most recognizable of the August birthstones, celebrated for its distinctive and consistent color. Unlike many gemstones that form deep within the Earth's crust, peridot has a unique geological origin. It crystallizes in the Earth's upper mantle and is brought to the surface by volcanic activity. This process can occur in two primary ways: through volcanic eruptions that carry the gems in hardened lava, or through tectonic activity that fractures the crust, allowing the olivine-rich mantle material to rise. Some peridot is also found in pallasite meteorites, offering a connection to outer space and making it one of the few gems with extraterrestrial origins.
The history of peridot is long and often confused with other gems. The word “peridot” is believed to derive from the Arabic faridat, meaning "gem." Throughout history, peridot has frequently been mistaken for other stones, most notably topaz and emerald. The Red Sea island of Topazios, a source that gave its name to 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. The 200 carats of gems decorating the shrine were long believed to be emeralds but are, in fact, peridot. Some historians even speculate that Cleopatra’s famous emerald collection may have been comprised of peridot, further cementing its long-standing misidentification with the prized green beryl.
Peridot's appeal is not only due to its color but also its perceived metaphysical properties. It is often associated with strength, protection, and prosperity. Its vibrant, sunlit hue is said to bring joy and peace, making it a popular choice for those seeking positive energy. In terms of gemological properties, peridot is a relatively durable stone, with a Mohs hardness of 6.5 to 7, making it suitable for various types of jewelry, including rings, provided it is cared for properly.
The Rediscovered Gem: Spinel's Journey from Mistaken Identity to Official Recognition
Spinel is the newest official August birthstone, added to the list in 2016 by the American Gem Trade Association and Jewelers of America. This addition was a long-overdue recognition of a gem that had been historically underappreciated and frequently mistaken for ruby. For centuries, magnificent red spinels were misidentified as rubies, with some of the world's most famous "rubies" actually being spinel. The goal of the 2016 update was to spotlight this lesser-known but stunning gem, giving August-born individuals a broader palette of colors to choose from.
Spinel takes its name from the Latin word spina, meaning "thorn," a reference to its pointed, thorn-like crystal form. It occurs in a wide range of colors, from the classic ruby-red to ballet-pink, hot-pink, cobalt blue, lavender, and even steely gray. This incredible color variety is one of spinel's greatest assets, offering a "hidden gem" for collectors and jewelry designers seeking something unique. Its addition to the birthstone list reflects a modern desire for alternatives and a deeper appreciation for gems beyond the traditional "big four."
Geologically, spinel forms under high-temperature and low-pressure conditions, often in metamorphic rocks. Significant sources include Myanmar (Burma), which has historically produced some of the finest red spinels, as well as Vietnam, Tanzania, and Sri Lanka. The Luc Yen region in northern Vietnam, for example, has produced spinel in deep red, purple, pink, violet, and violet-blue since the 1980s, with vivid blue spinels discovered there in the 2000s. A 2007 discovery in Tanzania of pinkish and orangy-red spinel captivated gem collectors, and mines there also produce purple and blue hues. Reaching these mines can be an adventure, often requiring long drives and hiking, underscoring the effort involved in bringing these gems to market.
In terms of durability, spinel is an excellent choice for jewelry. It ranks 8 on the Mohs scale of hardness, making it typically durable for rings and other items subject to wear. It is stable when exposed to light and most chemicals, though high heat can cause some colors to fade. For cleaning, spinel can generally be cleaned with ultrasonic and steam cleaners, but if the stone has fractures, warm soapy water is always a safer alternative. Its combination of durability, brilliant color, and relative rarity makes it a prized gem for modern jewelry.
Gemological Properties: A Comparative Overview
To better understand the unique characteristics of each August birthstone, a comparison of their key gemological properties is useful. The following table summarizes data based on the provided sources, highlighting the differences in hardness, composition, and notable features.
| Gemstone | Mineral | Mohs Hardness | Chemical Composition | Key Colors | Notable Properties |
|---|---|---|---|---|---|
| Peridot | Olivine | 6.5 - 7 | (Mg, Fe)₂SiO₄ | Yellowish-green to greenish-yellow | Forms in the upper mantle; found in volcanic lava and meteorites; historically confused with emerald. |
| Spinel | Spinel | 8 | MgAl₂O₄ | Red, pink, blue, purple, violet, gray | Often mistaken for ruby; wide color range; durable and stable under light. |
| Sardonyx | Chalcedony (Quartz) | 6.5 - 7 | SiO₂ | Bands of brownish-red (sard) and white/black (onyx) | A banded cryptocrystalline quartz; popular for ancient Roman seals and cameos; color may be dyed. |
This comparison reveals the diversity within August's birthstones. While peridot and sardonyx share a similar hardness range, spinel is notably harder and more durable. Their chemical compositions are entirely different, reflecting their unique geological origins. Peridot is a silicate mineral formed in the mantle, spinel is an oxide mineral, and sardonyx is a variety of quartz, one of the most common minerals on Earth. This scientific diversity is mirrored in their historical and cultural significance.
Symbolism and Metaphysical Beliefs
Each of the three August birthstones carries its own set of symbolic meanings and metaphysical beliefs, often rooted in ancient traditions and folklore.
Sardonyx, with its long history, is strongly associated with courage, happiness, and clear communication. Its use in ancient Roman seals and signet rings links it to authority and personal expression. The belief that it promotes stability in marriage and relationships persists today. As a stone of Venus and Mars in ancient Rome, it was believed to offer protection and harness the power of love and war, making it a talisman for both personal and martial endeavors.
Peridot is often linked to strength, protection, and prosperity. Its vibrant green color, reminiscent of new growth, is thought to bring joy, peace, and good fortune. Some traditions associate it with the sun, believing it to ward off evil spirits and protect the wearer from harm. Its historical connection to Cleopatra and the treasures of the Cologne Cathedral adds a layer of royal and sacred mystique to its symbolism.
Spinel, being the newest official birthstone, has a more modern symbolic profile, though it has been valued for centuries. Its wide array of colors allows for a broad range of meanings. Red spinel, often mistaken for ruby, carries the symbolism of passion, vitality, and energy, similar to ruby. Pink spinel may represent love and compassion, while blue spinel can symbolize calm and clarity. Its recent elevation to official birthstone status has also made it a symbol of rediscovery and the appreciation of overlooked beauty.
Care and Cleaning Instructions
Proper care is essential to maintain the beauty and longevity of any gemstone. The physical properties of each August birthstone dictate specific cleaning and handling guidelines.
Peridot, with a hardness of 6.5 to 7, is moderately durable but can be scratched by harder materials. It should be cleaned with warm, soapy water and a soft brush. Avoid sudden temperature changes and harsh chemicals, as peridot can be sensitive to thermal shock. Ultrasonic cleaners are generally not recommended, especially if the stone has inclusions or fractures.
Spinel is the most durable of the three, with a hardness of 8. It is stable and resistant to most chemicals and light exposure. Ultrasonic and steam cleaners are typically safe for spinel, but caution is advised if the stone has fractures. Warm soapy water is always a safe and effective method for cleaning. While it is heat-resistant, some colors may fade under high heat, so it is best to avoid prolonged exposure to extreme temperatures.
Sardonyx, like peridot, has a hardness of 6.5 to 7. It can be cleaned with warm, soapy water and a soft brush. However, a critical consideration for sardonyx is that it is often treated with dyes to enhance its color. Dyed sardonyx should not be soaked in water, as this can cause the dye to leach out. Therefore, it is important to know whether a sardonyx gemstone is untreated or dyed before cleaning it. For dyed stones, a quick, gentle wipe with a damp cloth is the safest method.
Conclusion
The three birthstones of August—Peridot, Spinel, and Sardonyx—offer a remarkable journey through geology, history, and symbolism. Sardonyx provides a tangible link to the ancient world, with its banded structure and practical use in Roman seals. Peridot, born from the intense conditions of the Earth's mantle and even from outer space, captivates with its consistent and vibrant green hue. Spinel, once the "hidden gem" mistaken for ruby, now shines in its own right, offering a rainbow of colors and exceptional durability. Together, they represent a unique triad in the birthstone calendar, providing August-born individuals with a rich selection of gems that are as diverse in their stories as they are in their appearance. Whether chosen for their historical significance, geological intrigue, or aesthetic beauty, each of these stones carries a legacy that makes it a worthy and meaningful treasure.