The month of August is uniquely distinguished within the calendar of birthstones by offering a trio of distinct and historically rich gemstones. While many months have evolved to include alternative stones, August presents a curated collection of three official options, each celebrated for its unique color, lore, and geological origin. The primary gemstone is the vibrant green peridot, a gem forged in the fiery crucible of the Earth's mantle and often brought to the surface by volcanic activity. Alongside peridot, the month is also represented by sardonyx, a banded variety of chalcedony with ancient roots, and spinel, a dazzling and often-overlooked gem that has been mistaken for ruby and sapphire throughout history.
These three stones offer a remarkable spectrum of choice, from the bright, summery lime green of peridot to the earthy, striped patterns of sardonyx and the brilliant sparkle of spinel in hues of red, pink, and blue. This variety allows those born in August to select a gem that not only reflects their personal style but also resonates with specific symbolic meanings. This article will provide a comprehensive exploration of each of August’s birthstones, delving into their geological formation, historical significance, gemological properties, and the symbolic beliefs that have made them cherished for millennia.
History and Lore
The historical narratives of August's birthstones are as diverse as their appearances, spanning ancient civilizations, royal courts, and modern gemological standardization.
Peridot: The Gem of the Sun
Peridot boasts one of the most ancient histories of any gemstone. It was prized by Egyptian pharaohs, who referred to it as the "gem of the sun" and believed it held protective qualities, warding off nightmares and evil spirits. Its rich green hue was so revered that it was often mistaken for emerald; indeed, Cleopatra's famed emerald collection is now believed by many gemologists to have been largely composed of peridot. The Egyptians mined this stone on the island of Zabargad in the Red Sea for thousands of years. Peridot was also a favorite of pirates, who called it the "Evening Emerald" and believed it could illuminate the night and protect them from evil. In more recent history, peridot was brought back to Europe by the Crusaders, who used it in church ornaments. Large quantities of peridot were mined in Egypt, and some of these gems can still be found adorning religious artifacts in museums today.
Sardonyx: The Stone of Courage
Sardonyx is the traditional birthstone for August and has a history deeply rooted in the ancient world. As a variety of banded chalcedony, its name derives from the Greek words "sard" and "onyx," meaning reddish-brown and veined stone. This gem was highly favored by the Romans, who used it extensively for cameos and intaglios, carving intricate scenes and figures into its layered bands. They believed sardonyx could bestow courage, strength, and victory in battle, and soldiers often wore it as an amulet for protection. For centuries, sardonyx has been a popular choice for signet rings, as its distinct bands provided a striking contrast for engraved designs, making it both a functional and symbolic piece of jewelry.
Spinel: The Great Impostor
Spinel's history is one of mistaken identity and overlooked brilliance. For centuries, spinel was confused with more precious gemstones, most notably ruby. Some of the world's most famous "rubies," such as the Black Prince's Ruby and the Timur Ruby in the British Crown Jewels, are, in fact, magnificent red spinels. These stones were mined in the Kuh-i-Lal region of Tajikistan and were highly valued by emperors and kings. The name "spinel" is derived from the Latin word spina, meaning "thorn," a reference to the typical shape of its crystals. Only in the late 18th century was spinel recognized as a distinct mineral species. Despite its long history of being mistaken for other gems, spinel has recently gained the recognition it deserves as a beautiful and valuable gemstone in its own right, officially joining the August birthstone list in 2016.
Geological Formation and Sources
The origins of these three gemstones are as varied as their histories, reflecting different geological processes and locations around the globe.
Peridot
Peridot has a unique origin among gemstones. It is one of the few gems formed not in the Earth's crust but deep within the mantle, the layer of molten rock beneath the tectonic plates. It is brought to the surface through volcanic activity. This process can also occur on a cosmic scale; small grains of peridot have been found in meteorites that have fallen to Earth, making it an extraterrestrial as well as terrestrial gem. Historically, the primary source of peridot was the island of Zabargad in the Red Sea. Today, significant deposits are found in Pakistan, Myanmar, and the United States (Arizona).
Sardonyx
Sardonyx is a variety of banded chalcedony, which is itself a form of quartz. It forms when layers of sard (a reddish-brown chalcedony) alternate with layers of onyx (a black or white chalcedony). This banding is a result of the conditions during its formation in volcanic rock cavities. While sources for sardonyx are not detailed in the provided materials, chalcedony deposits are widespread globally.
Spinel
Spinel is a magnesium aluminum oxide with a hardness of 8 on the Mohs scale. It forms under high-temperature and low-pressure conditions in metamorphic rocks and in certain types of sedimentary deposits. Historically, the most famous source of red spinel was the Kuh-i-Lal region in Tajikistan, near the Pamir Mountains. This region supplied the large red spinels that were traded along the Silk Road and eventually found their way into the crowns and jewels of Asian and European royalty.
Gemological Properties
Understanding the physical and chemical properties of each stone is essential for identification, valuation, and care.
| Gemstone | Chemical Composition | Hardness (Mohs Scale) | Key Characteristics |
|---|---|---|---|
| Peridot | (Mg, Fe)₂SiO₄ | 6.5 - 7 | Olivine mineral; distinct lime-green color; double refraction. |
| Spinel | MgAl₂O₄ | 8 | Single refraction; excellent brilliance; wide color range. |
| Sardonyx | SiO₂ (Quartz) | 7 | Banded chalcedony; alternating layers of reddish-brown and white/black. |
Peridot
Peridot is the gem-quality variety of the mineral olivine, with the chemical formula (Mg, Fe)₂SiO₄. Its characteristic green color comes from the presence of iron. It typically has a hardness of 6.5 to 7 on the Mohs scale, making it durable enough for most jewelry, though it can be prone to chipping if knocked hard. A key gemological feature of peridot is that it is singly refractive, but it exhibits strong double refraction, which can be detected with a loupe. High-quality peridot is valued for its vibrant, saturated green color with minimal inclusions.
Spinel
Spinel is a magnesium aluminum oxide (MgAl₂O₄) and is known for its exceptional hardness of 8 on the Mohs scale, making it a very durable and excellent choice for all types of jewelry. It is a singly refractive gemstone, similar to diamond and ruby, which contributes to its high brilliance and clarity. Spinel occurs in a vast array of colors, including vivid red, vibrant pink, orange, blue, and even black. The red and pink varieties are the most popular and are often compared to ruby and sapphire, but their single refraction helps gemologists distinguish them.
Sardonyx
Sardonyx is a banded variety of the mineral chalcedony, which is a microcrystalline form of quartz (SiO₂). It has a hardness of 7 on the Mohs scale, making it a relatively hard and durable stone, suitable for carving and cabochon cuts. Its defining feature is the sharp contrast between its layers of reddish-brown sard and white or black onyx. These parallel bands are what make sardonyx so distinctive and ideal for use in cameos and intaglios.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, all three of August's birthstones are rich in symbolic meaning and are believed to possess metaphysical properties.
- Peridot: Known as a stone of positivity and joy, peridot is believed to promote harmony for the mind, body, and spirit. It is associated with abundance, prosperity, and protection. Many believe it can help release negative patterns and open the heart to love and new beginnings. Its bright energy is thought to boost mood and confidence.
- Spinel: Spinel is a stone of renewal and revitalization. It is associated with high energy, inspiration, and vitality. It is believed to help restore energy, inspire hope, and provide encouragement during difficult times. Different colors of spinel may be associated with different chakras or intentions, but its overall energy is one of rejuvenation.
- Sardonyx: As a deeply grounding stone, sardonyx is associated with stability, strength, and courage. It is believed to provide protection and support for stable relationships. Its earthy energy helps to instill discipline and determination, making it a popular choice for those seeking to overcome challenges with fortitude.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of any gemstone. The different hardness levels and chemical compositions of August's birthstones require specific cleaning methods.
- Peridot (Hardness 6.5-7): Due to its moderate hardness and potential for chemical sensitivity, peridot should be cleaned with warm, soapy water and a soft brush. Avoid harsh chemicals, including acids and extreme temperature changes, as they can damage the stone. Ultrasonic and steam cleaners are generally not recommended.
- Spinel (Hardness 8): Spinel's high hardness makes it quite durable and easy to care for. It can be safely cleaned using warm, soapy water, an ultrasonic cleaner, and a steam cleaner. It is resistant to most chemicals.
- Sardonyx (Hardness 7): As a variety of quartz, sardonyx is also durable. It can be cleaned with warm, soapy water and a soft brush. It is generally safe to use an ultrasonic cleaner, but caution is advised if the stone has been treated or set in a fragile mounting.
Conclusion
The birthstones of August—peridot, spinel, and sardonyx—offer a remarkable trinity of choice, color, and meaning. From the volcanic origins and sun-drenched lore of peridot to the ancient Roman symbolism of sardonyx and the royal, misidentified history of spinel, each gem tells a unique story. Whether one is drawn to the vibrant green of summer embodied by peridot, the earthy strength of sardonyx, or the brilliant, revitalizing sparkle of spinel, August-born individuals have the rare privilege of selecting from a collection of stones that are as diverse and captivating as the month itself. Their enduring legacy in both history and modern jewelry ensures that these gems will continue to be celebrated for generations to come.