August is a unique month in the gemological calendar, boasting not one, but three official birthstones that offer a remarkable spectrum of color, history, and meaning. Those born in this summer month are fortunate to choose from the vibrant, lime-green hues of Peridot, the striking, contrasting bands of Sardonyx, or the brilliant, multifaceted sparkle of Spinel. This trio represents a fascinating journey through geological time—from the depths of the Earth’s mantle and the vastness of outer space to ancient volcanic eruptions. While Peridot is often celebrated as the primary gem for the month, the inclusion of Sardonyx and Spinel provides a rich palette for personal expression and a deeper connection to history.
The modern selection of August birthstones is a result of evolving traditions and a desire to offer variety in color, availability, and price. Sardonyx, with its ancient legacy, stands as the traditional anchor, while Peridot has held its official status since the early 20th century. Spinel, the most recent addition, was officially recognized in 2016, finally granting this long-overlooked gem its own celebrated place in the birthstone roster. This article will explore the distinct characteristics of each of these three magnificent gems, delving into their geological origins, gemological properties, historical lore, and the symbolism that makes them enduring choices for those born in August.
The Primary Gem: Peridot, The Sun Gem
Peridot is widely recognized as the principal August birthstone, a title it has held since the National Association of Jewelers (now Jewelers of America) standardized the modern birthstone list in 1912. Its most defining characteristic is its captivating color, a signature light green that ranges from a bright, lime hue to a deeper, olive tone. This distinctive color is not the result of trace impurities, as is common with many other colored gemstones, but is an intrinsic part of the gem’s fundamental chemical makeup.
Geological Formation and Origins
Peridot’s origin story is one of the most dramatic in the gem world. It is the gem-quality variety of the mineral olivine, with a chemical formula of (Mg,Fe)₂SiO₄. Its formation requires extreme conditions, occurring deep within the Earth’s mantle, far from the familiar processes that create most other gems. From these subterranean depths, Peridot is brought to the Earth’s surface through volcanic activity, often found embedded in the hardened lava that carried it on its journey.
Adding to its mystique, Peridot has also been identified in fallen meteorites, offering tangible proof of its existence beyond our planet. These extraterrestrial specimens, known as Pallasite Meteorites, are often too small for practical use in jewelry. However, the knowledge that Peridot exists both in the Earth’s mantle and in space contributes to its allure and its ancient nickname, the "sun gem." Most commercial Peridot today is sourced from volcanic regions, with significant deposits found in Arizona, Pakistan, and China. The finest specimens are prized for their natural brightness and do not typically require any enhancements.
Gemological Properties
Peridot possesses a unique set of physical characteristics that define its identity and value. Its color is its most celebrated attribute, with the most valued stones displaying a rich, saturated lime-green hue. The intensity of this color is directly dependent on the amount of iron present within its crystal structure.
In terms of durability, Peridot is a reasonably hard and resilient gem, making it suitable for various types of jewelry. It registers as 6.5 to 7 on the Mohs scale of hardness, which means it can withstand daily wear but is susceptible to scratching if handled roughly or stored with harder gems. It lacks cleavage, which is a significant advantage, as it reduces the risk of breakage when struck. However, it does have a tendency to fracture, so care should be taken to avoid sharp impacts.
History and Lore
Throughout history, Peridot has often been confused with other precious green stones, most notably emeralds. This confusion has led to some fascinating historical revelations. For instance, the 200 carats of gems adorning the Shrine of the Three Holy Kings in Germany’s Cologne Cathedral were believed for centuries to be emeralds but are, in fact, Peridot. Some historians even speculate that Cleopatra’s famous collection of emeralds may have actually consisted of Peridot.
The ancient Egyptians held Peridot in particularly high regard, calling it the "gem of the sun." They believed it protected its wearer from the terrors of the night and warded off evil spirits. It was also associated with prosperity, good fortune, and peace. Its ability to sparkle brilliantly under both natural and artificial light earned it the nickname "evening emerald," though it is important to distinguish it from true emerald. Its reputation for cleansing the mind of negativity and aiding friendship has persisted through the ages, making it a gem of both beauty and powerful meaning.
The Traditional Stone: Sardonyx, The Warrior's Gem
While Peridot may be the most well-known August stone today, Sardonyx holds the distinction of being the original and traditional birthstone for the month. This gem is not a single mineral but a variety of chalcedony, which is a form of quartz. Its defining feature is its dramatic banding, which creates a visually striking and powerful appearance.
Composition and Appearance
Sardonyx is a composite gem, a banded mixture of sard and onyx. Sard is the reddish-brown variety of chalcedony, while onyx is typically black or white. When these two minerals form together in alternating layers, they create the characteristic bands of reddish-brown and white (or sometimes black) that make Sardonyx so distinctive. The bands should be straight, parallel, and well-defined for the gem to be considered high quality. The contrast between the warm, earthy tones of the sard and the stark, clean lines of the onyx gives Sardonyx its unique and bold aesthetic.
Historical Significance and Symbolism
Sardonyx boasts a history that stretches back over 4,000 years, making it one of the earliest gems used for personal adornment and seals. Its name is derived from the Greek words "sard" (meaning reddish-brown) and "onyx" (meaning nail or claw). In ancient Rome, Sardonyx was a favorite stone for signet rings. The wax used to seal important documents would not stick to its smooth, non-porous surface, making it a practical and prestigious choice for official seals.
Beyond its practical use, Sardonyx was revered for its symbolic properties. It was considered a stone of strength, protection, and courage. Roman soldiers would wear amulets of Sardonyx into battle, believing it would grant them bravery and shield them from harm. It was also associated with happiness and clear communication, making it a popular talisman for public speakers and leaders. Its enduring legacy as a symbol of strength and stability makes it a meaningful, if less common, choice for a modern August birthstone.
The Modern Sparkler: Spinel, The Great Impostor
Spinel is the newest addition to the August birthstone family, officially added to the list by the American Gem Trade Association (AGTA) in 2016. Its inclusion was a long-overdue recognition of a gem that has been mistaken for some of the world’s most valuable stones for centuries. Spinel offers an incredible range of colors and a brilliance that rivals that of any top-tier gemstone.
A History of Mistaken Identity
For hundreds of years, red Spinel was the "great impostor," masquerading as ruby in the crowns and jewels of royalty and aristocrats. Some of the world’s most famous "rubies" are, in fact, giant Spinels. The Black Prince’s Ruby, a massive 170-carat red gem set in the British Imperial State Crown, is the most famous example. Similarly, the Timur Ruby, a 361-carat red gem now in the collection of the British Crown Jewels, was also long thought to be a ruby before being identified as Spinel.
This case of mistaken identity was largely due to the fact that red Spinel and ruby are both composed of aluminum oxide (though Spinel’s formula is MgAl₂O₄, while ruby’s is Al₂O₃), are found in similar geological environments, and share nearly identical hardness and refractive properties. Only in the 19th century did gemologists develop the tools to distinguish between the two, finally allowing Spinel to be appreciated for its own unique merits.
Gemological Properties and Color Range
Spinel is a magnesium aluminum oxide and is renowned for its exceptional hardness (8 on the Mohs scale) and lack of cleavage, making it an extremely durable and wearable gemstone. While it is most famous for its vivid red varieties, which can rival the finest rubies, Spinel appears in a dazzling array of colors. It is found in brilliant pinks, vibrant oranges, rich purples, and even stunning blues. This color diversity, combined with its brilliance and durability, makes it an incredibly versatile gem for jewelry designers and a compelling choice for an August birthstone.
Symbolism and Renewal
While Spinel’s recent designation as a birthstone means it lacks the ancient lore of Peridot or Sardonyx, it has quickly developed its own modern symbolism. Its remarkable range of colors and its "rebirth" as a recognized gem in its own right have linked it to concepts of renewal, revitalization, and vitality. Its dazzling sparkle and energetic presence make it a stone that inspires passion and joy, a perfect representation for the vibrant energy of late summer.
Choosing and Caring for August Birthstones
With three distinct options, choosing an August birthstone is a matter of personal preference, lifestyle, and budget. Each stone offers a different combination of durability, color, and historical weight.
For the Lover of History and Symbolism: Sardonyx is an excellent choice. Its ancient heritage and association with strength and protection give it a profound sense of gravitas. While it is a durable stone (7 on the Mohs scale), its banding can sometimes include softer or more fragile zones, so it is best suited for pieces that are not subject to heavy wear, such as pendants or earrings.
For the Seeker of Natural Beauty and Uniqueness: Peridot is the ideal gem. Its signature green color is instantly recognizable, and its origin story—born from volcanoes and found in meteorites—is unparalleled. With a hardness of 6.5 to 7, it is suitable for most jewelry, but owners should be mindful of its tendency to fracture. It is best cleaned with warm, soapy water and a soft brush, avoiding harsh chemicals and extreme temperature changes.
For the Fan of Brilliance and Versatility: Spinel is the perfect option. Offering exceptional hardness (8 on the Mohs scale) and a spectacular range of colors, it is a durable and brilliant gem suitable for any type of jewelry. It is relatively easy to care for, requiring only standard cleaning methods with warm, soapy water and a soft cloth. Its ability to provide a high-end look at a more accessible price point than ruby or sapphire makes it a savvy choice.
Conclusion
The August birthstones—Peridot, Sardonyx, and Spinel—offer a remarkable trio of choices that celebrate the month’s unique character. From the sun-kissed green of Peridot, a gem of ancient lore forged in the Earth’s fiery heart, to the courageous bands of Sardonyx, the original seal of Roman warriors, and the dazzling, long-misunderstood brilliance of Spinel, each stone tells a distinct story. Together, they provide a palette that ranges from the earthy and historic to the vibrant and modern. For anyone born in August, these gems are more than just beautiful adornments; they are symbols of strength, renewal, and a connection to the powerful forces of nature and history.