August, the month of summer’s peak, is adorned with three distinct birthstones—peridot, spinel, and sardonyx—each carrying a unique story of geological origin, historical significance, and symbolic meaning. While peridot is widely recognized as the primary August birthstone, the inclusion of spinel and sardonyx adds richness and diversity to the month’s gemstone heritage. These stones have graced jewelry and talismans for millennia, each contributing to the cultural and spiritual traditions of the people who have cherished them.
This article explores the gemological properties, historical contexts, and symbolic meanings of the three August birthstones, drawing on centuries of use and recent rediscovery. The discussion is grounded in the information provided by reputable sources and offers insights into the enduring appeal of these gems in both historical and contemporary contexts.
History and Lore
The historical roots of the August birthstones stretch back thousands of years, with peridot being the most ancient of the three. Known as the “gem of the sun” by the ancient Egyptians, peridot was believed to possess protective powers and was used as a talisman against evil spirits and “terrors of the night.” The Egyptians mined peridot on the island of Zabargad in the Red Sea, a site so harsh it was known as the “Island of Death.” The gem’s association with light and positivity was so strong that it was often used in religious and ceremonial contexts.
Peridot's journey through history is also reflected in its misidentifications. The gem was frequently confused with emerald and topaz due to its vivid green hue and the conditions under which it was found. For example, the Shrine of the Three Holy Kings in Cologne Cathedral was believed to be adorned with emeralds, but these were, in fact, peridots. Some historians speculate that Cleopatra’s famous emerald collection may have been composed of peridots as well, further illustrating the gem's historical significance and its role in the adornment of powerful and influential figures.
Spinels, on the other hand, have a more recent emergence in the world of gemstones. Historically, they were often mistaken for rubies and sapphires due to their vibrant red and blue hues. However, in 2016, spinel was officially recognized as a modern August birthstone, a testament to its growing appreciation and recognition in the gemstone community. This relatively recent acknowledgment underscores the dynamic nature of birthstone traditions, which continue to evolve with new discoveries and changing trends.
Sardonyx, the original August birthstone, has a history dating back over 4,000 years. This banded stone, composed of layers of sard (a type of red quartz) and onyx, has been used in amulets, seals, and cameos by ancient Greeks and Romans. Sardonyx was believed to bring victory in battle and enhance communication skills, making it a favored stone among warriors and orators. Its durability and aesthetic appeal have made it a popular choice for engraving and carving, and it continues to be valued for its historical and symbolic significance.
Geological Formation and Sources
The geological origins of the August birthstones are as diverse as their histories. Peridot, the gem variety of the mineral olivine, is formed under extreme conditions deep within the Earth’s mantle. It is brought to the surface through volcanic activity or, in rare cases, via meteorites. The presence of iron in peridot is responsible for its characteristic green color, which can range from a pale lime green to a deep olive hue. The most notable historical source of peridot is the island of Zabargad in the Red Sea, where mining began around 340–279 BCE. Today, peridot is mined in various locations including China, Myanmar, Pakistan, Tanzania, Vietnam, and the United States. The United States has a particularly unique source of peridot—Peridot Beach in Hawaii, where the sands are known for their luminous green shimmer.
Spinels are formed in metamorphic and igneous rocks and are typically found in regions with high-temperature geological processes. The most famous spinel deposits are located in Burma (Myanmar), Thailand, and Sri Lanka. Red spinels from Burma are particularly prized for their vivid color and clarity, and they have been historically confused with rubies. The distinction between spinel and ruby was only made possible with advances in gemological science, and the recognition of spinel as a separate and valuable gemstone has grown in recent years.
Sardonyx is a type of chalcedony, a microcrystalline quartz, and is formed through the deposition of silica in sedimentary and volcanic rocks. It is found in various parts of the world, including India, Brazil, and the United States. The alternating bands of red and white in sardonyx are the result of the presence of iron and silica. The stone’s durability and ease of carving have made it a popular choice for seals and cameos in both ancient and modern times.
Gemological Properties
Understanding the gemological properties of the August birthstones is essential for appreciating their beauty and durability. Each stone has distinct characteristics that influence its use in jewelry and its care requirements.
Peridot is known for its range of green hues, from yellowish lime green to deep olive. Its color is due to the presence of iron, and it is one of the few gemstones that consistently retains its color under various lighting conditions. Peridot has a hardness of 6.5 to 7 on the Mohs scale, which makes it relatively durable but still susceptible to scratches and damage from hard materials. It has a refractive index of 1.65 to 1.70 and is singly refractive. Peridot is also notable for its pleochroism, meaning it can display different colors when viewed from different angles. It is typically cut into faceted stones to enhance its brilliance and color.
Spinel is a mineral species that can occur in a wide range of colors, including red, blue, pink, and black. The red spinels from Burma are particularly renowned for their deep, vibrant color and clarity. Spinel has a hardness of 8 on the Mohs scale, making it more durable than peridot and suitable for everyday wear. It has a refractive index of 1.718 to 1.737 and is doubly refractive. Spinel is often cut into round, oval, or cushion shapes to maximize its brilliance and color. Its versatility in color and clarity has made it a popular alternative to ruby and sapphire in jewelry design.
Sardonyx is a banded form of chalcedony, with layers of red sard and white onyx. Its color is due to the presence of iron and silica. Sardonyx has a hardness of 6.5 to 7 on the Mohs scale, making it relatively durable but still requiring careful handling. It is typically cut into cabochons or beads and is often carved into cameos and seals due to its ability to take a high polish. Sardonyx is not as brilliant as faceted stones but has a smooth, even luster that is attractive in its own right.
Symbolism and Metaphysical Beliefs
The August birthstones have long been associated with various symbolic and metaphysical beliefs, reflecting their historical use and cultural significance. These beliefs have evolved over time but continue to influence the perception and use of these gemstones in jewelry and spiritual practices.
Peridot is often referred to as the “stone of compassion” and is believed to bring good health, restful sleep, and peace to relationships. Its green color is associated with nature, renewal, and youthfulness. Peridot is also believed to calm anger and promote emotional balance. In ancient Egypt, peridot was considered a protective talisman against evil spirits and was used in religious and ceremonial contexts. It is also associated with mental focus and perseverance, making it a popular stone among students and scholars.
Spinels are known for their vibrant colors and are often associated with passion, energy, and vitality. Red spinels are believed to enhance courage and vitality, while blue spinels are associated with calmness and clarity. Spinels are also believed to enhance communication and emotional expression, making them a popular choice for those seeking to improve their interpersonal relationships. The recognition of spinel as a modern August birthstone has brought renewed attention to its symbolic and metaphysical properties.
Sardonyx has been historically associated with strength, courage, and protection. It is believed to bring victory in battle and enhance communication skills, making it a favored stone among warriors and orators. Sardonyx is also believed to provide protection against negative influences and to promote confidence and assertiveness. Its banded appearance is thought to symbolize balance and harmony, and it is often used in amulets and seals to enhance these qualities.
Care and Cleaning
Proper care and cleaning are essential for maintaining the beauty and longevity of August birthstone jewelry. Each stone has specific requirements based on its hardness, refractive properties, and susceptibility to damage.
Peridot should be cleaned with a soft, lint-free cloth and mild soap. It is important to avoid harsh chemicals and ultrasonic cleaners, as these can damage the stone. Peridot should also be stored separately from harder gemstones to prevent scratches. Due to its relatively low hardness, peridot is best suited for jewelry that is worn occasionally rather than everyday use.
Spinel is more durable than peridot and can be cleaned with a soft cloth, mild soap, and lukewarm water. Ultrasonic and steam cleaners are generally safe for spinel, but it is important to check with a professional jeweler to ensure compatibility. Spinel can be worn daily due to its hardness, but care should be taken to avoid exposure to hard materials that could cause scratches.
Sardonyx can be cleaned with a soft cloth and mild soap. It is relatively durable but should be handled with care to avoid chips and scratches. Sardonyx should be stored separately from harder gemstones to prevent damage. Due to its banded structure, sardonyx is best suited for cabochons and beads rather than faceted cuts.
Conclusion
The August birthstones—peridot, spinel, and sardonyx—each carry a rich legacy of geological formation, historical significance, and symbolic meaning. Peridot, the most ancient of the three, has been cherished for millennia for its protective powers and vibrant green color. Spinel, once mistaken for ruby and sapphire, has recently gained recognition as a modern birthstone, adding a new dimension to August’s gemstone heritage. Sardonyx, the original August birthstone, continues to be valued for its durability and symbolic associations with strength and protection.
These gemstones not only serve as beautiful adornments but also as meaningful symbols of personal significance and cultural tradition. Whether chosen for their historical ties, metaphysical properties, or aesthetic appeal, the August birthstones continue to captivate and inspire those who wear them. Understanding their properties, origins, and meanings allows for a deeper appreciation of these gems and the enduring legacy they represent in the world of gemology and jewelry.