August is a unique month in the world of gemology, distinguished by its celebration of not one, but three distinct and officially recognized birthstones. This multiplicity offers individuals born in the height of summer a remarkable breadth of choice, encompassing a wide spectrum of colors, historical depths, and symbolic meanings. The official August birthstones—Peridot, Spinel, and Sardonyx—each possess a unique identity, from the radiant green of Peridot to the fiery versatility of Spinel and the earthy, banded elegance of Sardonyx. This guide delves into the rich tapestry of history, geology, and symbolism that defines these three exceptional gems, providing a comprehensive resource for gemstone enthusiasts, collectors, and anyone seeking to understand the legacy of the August birthstones.
The journey to this trio of gems was a gradual one. While Sardonyx served as the traditional August stone for centuries, the modern list was formalized in 1912 with the establishment of the birthstone list by the National Association of Jewelers (now the American Gem Trade Association). This list initially named Peridot as the official August birthstone. More recently, in 2016, the American Gem Trade Association and Jewelers of America officially added Spinel to the roster, acknowledging its beauty, durability, and growing popularity. This evolution reflects a desire to provide more options in terms of color, affordability, and availability, ensuring that every August-born individual can find a gem that resonates with their personal style and spirit.
History and Lore
The historical narratives of the August birthstones are as varied as the gems themselves, spanning ancient civilizations, royal treasuries, and religious traditions.
Peridot: The Gem of the Sun
Peridot boasts one of the most storied histories among gemstones, with evidence of its use dating back to ancient Egypt. The Egyptians held this vibrant green gem in high regard, mining it on the island of Zabargad in the Red Sea, a source that was known for producing exceptional quality stones. So cherished was Peridot that the Egyptians referred to it as the "gem of the sun." They believed it possessed protective qualities, warding off nightmares and evil spirits. A remarkable attribute of Peridot, noted in historical accounts, is its ability to glow in the dark, a characteristic that likely contributed to its mystical reputation. Ancient lore suggests that Peridot was a favorite stone of the Hawaiian goddess Pele, who was said to have created the islands' volcanic landscapes and adorned them with tears of her gem.
Spinel: The Great Impostor and a Royal Treasure
For centuries, Spinel was overshadowed by its more famous relative, the ruby. Many of the world's most legendary "rubies," including the 170-carat "Black Prince's Ruby" in the British Imperial State Crown and the 398-carat "Timur Ruby," were, in fact, magnificent red spinels. These magnificent stones were often mistaken for rubies due to their similar color and were highly prized by royalty and collectors alike. It was not until the 18th century that mineralogists began to reliably distinguish spinel from ruby, recognizing it as a distinct mineral species with its own unique properties. The name "spinel" is believed to derive from the Greek word "spinos," meaning "spark," a fitting tribute to its brilliant luster. Beyond its royal connections, Spinel has been found in the gem treasuries of ancient civilizations, suggesting it was valued in its own right long before its true identity was widely understood.
Sardonyx: The Stone of Strength and Oratory
Sardonyx, with its striking bands of reddish-brown and white, is perhaps the most ancient of the August stones in terms of its symbolic use. It is a variety of onyx, composed of layers of sard and alternating bands of chalcedony. The use of Sardonyx as a gemstone and for carving intricate cameos and intaglios dates back to ancient Greece and Rome. Roman soldiers would wear Sardonyx rings and amulets carved with images of Mars, the god of war, believing the stone would grant them courage and protection in battle. The stone was also highly valued by orators. It was believed that a Sardonyx amulet could bestow eloquence and persuasive powers upon the wearer, making it a popular talisman for public speakers and leaders. Its name is a combination of "sard," referring to the reddish-brown layer, and "onyx," the Greek word for "claw" or "fingernail," which describes its banded appearance.
Geological Formation and Sources
Understanding the geological origins of these gems reveals the natural processes that create their unique structures and colors.
Peridot: A Gem from the Mantle
Peridot is unique among gemstones as it is formed deep within the Earth's mantle, not in the crust like most other gems. It crystallizes under extreme heat and pressure and is brought to the surface through volcanic activity. Its signature olive-green color is the result of its iron content. Unlike many other colored gems, the hue of Peridot is not caused by trace impurities but by the inherent presence of iron within its crystal structure. This makes it one of the few gemstones that naturally occurs in only one color family, though the shade can vary from yellow-green to deep olive depending on the iron levels. Historically, the primary source of fine Peridot was the island of Zabargad in the Red Sea. Today, significant sources include Pakistan, Arizona in the United States, and Myanmar.
Spinel: A Durable Classic
Spinel is a magnesium aluminum oxide that forms in the metamorphic rock of marble and alluvial deposits. It is often found in the same geological environments as ruby and sapphire, which explains why it has been so frequently confused with them. Spinel is prized for its excellent hardness (8 on the Mohs scale) and lack of cleavage, making it a very durable gem suitable for all types of jewelry. While it is found in many locations around the world, some of the most historically significant and finest quality red spinels have come from the famed marble quarries of Myanmar (Burma), Sri Lanka, and Thailand. It also occurs in a wide array of other colors, including vibrant blues, pinks, and the rare, highly sought-after "cobalt blue" spinel.
Sardonyx: A Variety of Chalcedony
Sardonyx is a banded variety of chalcedony, which is a microcrystalline form of quartz. It is composed of alternating layers of sard (a reddish-brown variety of chalcedony) and onyx (a black-and-white banded variety). The formation occurs in volcanic rock cavities, where silica-rich solutions deposit layers over long periods, creating the distinctive banding. Sardonyx is found in various parts of the world, including India, Brazil, Germany, and the United States. Its relatively soft nature (7 on the Mohs scale) and perfect cleavage in one direction require careful handling, but its unique patterns make it a favorite for carved cameos, intaglios, and cabochon cuts that highlight its natural bands.
Gemological Properties
The following table summarizes the key gemological properties of the three August birthstones, highlighting their distinct physical characteristics.
| Property | Peridot | Spinel | Sardonyx |
|---|---|---|---|
| Chemical Composition | (Mg,Fe)₂SiO₄ | MgAl₂O₄ | SiO₂ (Silicon Dioxide) |
| Color | Olive green, yellow-green | Wide range: red, pink, orange, purple, blue, black, colorless | Bands of reddish-brown (sard) and white (onyx) |
| Hardness (Mohs Scale) | 6.5 - 7 | 8 | 7 |
| Crystal System | Orthorhombic | Cubic | Trigonal (microcrystalline) |
| Refractive Index | 1.65 - 1.69 | 1.71 - 1.73 | 1.53 - 1.54 |
| Luster | Vitreous (glassy) | Vitreous (glassy) | Vitreous to waxy |
Peridot is distinguished by its single-color range, dictated by its iron content. Its hardness of 6.5 to 7 makes it moderately durable, but it can be prone to chipping if struck with force, so protective settings are recommended for rings.
Spinel is one of the most durable of the colored gemstones, with a hardness of 8 on the Mohs scale. This, combined with its excellent clarity and lack of cleavage, makes it an outstanding choice for jewelry that will be worn daily. Its refractive index is similar to that of ruby and sapphire, which contributes to its brilliance and the historical confusion between the stones.
Sardonyx, as a variety of chalcedony, has a hardness of 7 but possesses perfect cleavage in one direction, making it more susceptible to breakage than Spinel or Peridot. Its lower refractive index means it does not exhibit the same level of brilliance as the other two stones, but its value lies in its unique, bold banding, which is best displayed in cabochon cuts or intricate carvings.
Symbolism and Metaphysical Beliefs
Across cultures and through the ages, each of the August stones has accumulated a rich set of symbolic meanings and metaphysical beliefs.
Peridot: Joy and Protection
Peridot is widely associated with positivity, joy, and abundance. Its bright, fresh green color is seen as a symbol of growth, renewal, and the vibrant energy of summer. Metaphysically, Peridot is often linked to the heart chakra, where it is believed to promote emotional clarity, release negative patterns, and open the heart to love and forgiveness. It is also considered a powerful protective stone, a belief that harkens back to its ancient Egyptian use for warding off evil spirits and nightmares. Today, it is often used as a talisman for boosting confidence, attracting prosperity, and fostering a sense of well-being.
Spinel: Renewal and Inspiration
Spinel is a stone of revitalization and inspiration. Its wide range of colors allows it to be associated with various energies, but it is most often linked to renewing energy, inspiring hope, and encouraging perseverance through difficult times. Historically, its resemblance to ruby led to it being associated with vitality and passion. In modern crystal healing, Spinel is used to restore weariness, alleviate stress, and stimulate the mind towards new ideas and creative solutions. It is a stone of encouragement, believed to help one overcome challenges with renewed vigor and a positive outlook.
Sardonyx: Strength and Stability
As a stone with ancient warrior associations, Sardonyx is the quintessential gem of strength, courage, and protection. Its grounded, earthy tones are seen as a reflection of its stabilizing energy. It is believed to promote discipline, integrity, and steadfastness in one's personal and professional life. Sardonyx is also associated with stable, lasting relationships and is often used as a talisman for marital fidelity and enduring friendship. For those seeking to build a solid foundation in their lives, whether through enhancing willpower or providing a sense of security, Sardonyx is considered a powerful ally.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of any gemstone. The different properties of Peridot, Spinel, and Sardonyx require specific attention.
Peridot (Hardness 6.5-7, No Cleavage): Due to its moderate hardness, Peridot can be scratched by stones of higher hardness. It is advisable to store it separately from other jewelry. It can be cleaned safely with warm, soapy water and a soft brush. Avoid sudden temperature changes and exposure to harsh chemicals, including acids and strong household cleaners, as it can be damaged by them.
Spinel (Hardness 8, No Cleavage): Spinel is a very durable gemstone and is relatively easy to care for. It can be cleaned with warm, soapy water and a soft brush or an ultrasonic cleaner. It is generally stable when exposed to light and heat, making it a low-maintenance choice for everyday jewelry.
Sardonyx (Hardness 7, Perfect Cleavage): While Sardonyx has a good hardness, its perfect cleavage makes it vulnerable to breakage from a sharp blow. It should be protected from hard surfaces and stored carefully. Cleaning should be done with warm, soapy water and a soft brush. Avoid steam cleaners and ultrasonic cleaners, as the vibrations and heat could potentially cause damage along its cleavage planes.
Conclusion
The August birthstones—Peridot, Spinel, and Sardonyx—offer a remarkable trifecta of beauty, history, and meaning. Peridot captivates with its singular, radiant green, a color synonymous with summer and a history steeped in ancient Egyptian lore. Spinel provides a dazzling array of colors and the exceptional durability prized by royalty, long mistaken for the finest rubies. Sardonyx offers a connection to the ancient world with its bold, earthy bands, a symbol of strength and stability for millennia. Together, they provide August-born individuals with an unparalleled opportunity to select a gem that not only reflects their personality but also carries a legacy that spans from the depths of the Earth to the heights of human culture. Whether drawn to the joyful energy of Peridot, the revitalizing spirit of Spinel, or the grounding power of Sardonyx, there is a perfect August stone for everyone.