August’s birthstones—peridot, sardonyx, and spinel—represent a rare convergence of color, symbolism, and history in the world of gemology. While most months are associated with a single gemstone, August is distinguished by three distinct stones, each with its own unique characteristics and cultural significance. These stones have captivated gem lovers and historians alike for centuries, offering a rich tapestry of meanings and uses. From the vibrant green glow of peridot, often called the “sun gem,” to the bold striped patterns of sardonyx and the sparkling diversity of spinel, each gemstone contributes a distinct dimension to the August birthstone tradition.
This article delves into the historical, geological, and cultural significance of August’s birthstones, drawing from well-documented sources in gemology and historical studies. It explores the properties, symbolism, and care for each gem, offering a comprehensive guide for enthusiasts, jewelry buyers, and students of gemology.
History and Lore
The tradition of birthstones dates back to ancient civilizations, where gemstones were believed to hold protective and healing properties. The modern birthstone calendar, as it is known today, has evolved from these ancient beliefs and practices. The August birthstones—peridot, sardonyx, and spinel—each have unique historical narratives that contribute to their enduring appeal.
Peridot: The Sun Gem
Peridot has a storied past, with its earliest recorded use dating back to ancient Egypt. Known as the “gem of the sun,” peridot was revered for its vibrant green color and association with solar energy. The ancient Egyptians believed that peridot had the power to ward off nightmares and evil spirits. They also believed the stone was formed from the tears of a sun god or the solidified light of the sun itself.
Peridot was sometimes mistaken for emerald in medieval Europe, a fact that has led to the discovery of many peridots in historical royal collections. The gemstone’s association with the sun and its calming, positive energy made it a popular choice for jewelry and protective amulets.
Sardonyx: A Stone of Strength and Courage
Sardonyx, a banded chalcedony with distinctive red-brown and white stripes, has been used for millennia in various cultures. Its name is derived from the Greek “sardonyx,” which combines the names of sard (a reddish chalcedony) and onyx (a banded chalcedony). Sardonyx was particularly valued in ancient Rome and Greece, where it was used to carve seals and signet rings.
In these cultures, sardonyx was believed to bring courage, strength, and protection. It was also associated with the Roman god Mars, symbolizing the warrior spirit. The bold patterns of sardonyx made it ideal for engraving, and it was often used as a seal stone in important legal and governmental documents.
Spinel: A Hidden Gem
Spinel is one of the more recently recognized August birthstones, though it has a long and fascinating history. Known for its brilliant colors and high refractive index, spinel was often mistaken for ruby in ancient times. Some of the most famous “rubies” in royal collections are actually spinels.
Spinel was particularly valued in the Middle East and Asia, where it was considered a symbol of vitality and renewal. Its diverse color palette, ranging from deep red and pink to orange and even blue, made it a versatile gemstone for jewelry and adornment.
Geological Formation and Sources
Understanding the geological properties and sources of a gemstone provides insight into its rarity, quality, and value. August’s birthstones are no exception, with each having a unique formation process and geographic origin.
Peridot: A Product of the Earth’s Mantle
Peridot is a gem-quality variety of the mineral olivine, and it is one of the few gemstones that occurs in only one color—green. The color of peridot is due to the presence of iron within its crystal structure. The intensity of the green can vary from a yellowish-green to a deep olive, depending on the iron content.
Peridot is formed deep within the Earth’s mantle and is brought to the surface through volcanic activity or meteorite impacts. Some of the finest peridots have even been found in meteorites, making them extraterrestrial in origin. The most commercially significant sources of peridot today are Arizona, Pakistan, and China. Peridot is relatively durable, with a hardness of 6.5 to 7 on the Mohs scale, making it suitable for everyday wear in jewelry.
Sardonyx: A Banded Chalcedony
Sardonyx is a type of chalcedony, which is a cryptocrystalline form of quartz. It is composed of alternating bands of sard (a reddish-brown chalcedony) and onyx (a black or white chalcedony). The formation of sardonyx involves the deposition of silica-rich water in sedimentary rock layers, resulting in the distinctive banded appearance.
Sardonyx is typically found in sedimentary rock formations and is mined in various parts of the world, including India, Brazil, and the United States. It has a hardness of 6.5 to 7 on the Mohs scale, making it durable enough for use in jewelry. Its bold bands make it an attractive choice for engraved rings, pendants, and other ornamental pieces.
Spinel: A Versatile Gem
Spinel is a mineral that forms in a variety of colors due to trace elements within its crystal structure. The red and pink varieties are caused by the presence of chromium or magnesium, while other colors such as orange, blue, and even black can occur depending on the impurities present.
Spinel is typically formed in metamorphic and igneous rocks. It is found in several locations around the world, including Burma (Myanmar), Sri Lanka, Afghanistan, and Tanzania. Spinel has a hardness of 8 on the Mohs scale, making it a durable gemstone suitable for everyday wear. Its high refractive index and brilliance make it a popular choice for jewelry, especially in vintage and antique pieces.
Gemological Properties
Understanding the scientific properties of a gemstone is essential for determining its quality, durability, and value. The gemological properties of peridot, sardonyx, and spinel each contribute to their unique characteristics and uses in jewelry.
Peridot
- Chemical Composition: (Mg,Fe)₂SiO₄
- Hardness: 6.5–7 on the Mohs scale
- Color: Ranges from yellow-green to deep olive
- Luster: Vitreous (glassy)
- Clarity: Generally included, with some inclusions being typical for peridot
- Refractive Index: 1.65–1.70
- Specific Gravity: 3.3–4.5
Peridot is known for its vibrant green color and glassy luster. It is relatively soft compared to other gemstones, so it is important to avoid abrasive cleaning methods. Peridot is also sensitive to high heat and acid, so it should be cleaned with care.
Sardonyx
- Chemical Composition: SiO₂ (silicon dioxide)
- Hardness: 6.5–7 on the Mohs scale
- Color: Reddish-brown and white bands
- Luster: Waxy to vitreous
- Clarity: Typically opaque to translucent
- Refractive Index: 1.48–1.53
- Specific Gravity: 2.60–2.64
Sardonyx is a banded chalcedony with a waxy to vitreous luster. The bold, contrasting bands of red and white make it ideal for engraving and decorative purposes. Sardonyx is relatively durable and can be used in everyday jewelry.
Spinel
- Chemical Composition: MgAl₂O₄
- Hardness: 8 on the Mohs scale
- Color: Wide range including red, pink, orange, blue, and black
- Luster: Vitreous
- Clarity: Typically clear or slightly included
- Refractive Index: 1.718–1.725
- Specific Gravity: 3.6–4.0
Spinel is known for its high refractive index and brilliant colors. It is relatively durable and can be used in a variety of jewelry settings. Spinel is often cut into round brilliant or cushion shapes to enhance its brilliance.
Symbolism and Metaphysical Beliefs
Gemstones have long been associated with various symbolic meanings and metaphysical properties. August’s birthstones—peridot, sardonyx, and spinel—each carry their own unique symbolic significance and have been used in various cultures for protective and healing purposes.
Peridot: A Gem of Good Fortune and Healing
Peridot is often associated with positive energy, good fortune, and protection. It is believed to bring prosperity and success to those who wear it. In ancient Egypt, peridot was thought to ward off nightmares and evil spirits. The gemstone is also believed to promote health, peace, and harmony.
Peridot is particularly valued for its calming properties, making it a popular choice for those seeking emotional balance and mental clarity. It is also believed to aid in the management of anger and depression, making it a beneficial stone for those struggling with emotional issues.
Sardonyx: A Stone of Courage and Strength
Sardonyx is traditionally associated with courage, strength, and protection. In ancient Rome and Greece, it was believed to bring courage and strength to warriors and leaders. The bold, contrasting bands of red and white in sardonyx are thought to symbolize the balance between action and restraint, making it a powerful stone for those seeking to maintain balance in their lives.
Sardonyx is also believed to provide protection against negative influences and to help in the manifestation of goals and intentions. It is often used in talismans and amulets to provide strength and support during challenging times.
Spinel: A Stone of Renewal and Vitality
Spinel is associated with renewal, vitality, and emotional healing. It is believed to promote a sense of optimism and to help individuals move past emotional wounds and setbacks. The gemstone is particularly valued for its ability to bring energy and enthusiasm to those who wear it.
Spinel is also believed to enhance communication and to help individuals express themselves more clearly and confidently. It is a powerful stone for those seeking to improve their relationships and to foster a sense of connection and understanding.
Care and Cleaning
Proper care and cleaning are essential for maintaining the beauty and longevity of any gemstone. Each of August’s birthstones has specific care requirements based on its hardness, sensitivity to chemicals, and other physical properties.
Peridot
Peridot is relatively soft compared to other gemstones, with a hardness of 6.5–7 on the Mohs scale. It is also sensitive to high heat and acid, so it should be cleaned with care. To clean peridot, use a mild soap solution and a soft cloth or brush. Avoid ultrasonic cleaners and steamers, as they can cause damage. Store peridot separately from harder gemstones to prevent scratching.
Sardonyx
Sardonyx is relatively durable, with a hardness of 6.5–7 on the Mohs scale. It can be cleaned with a mild soap solution and a soft cloth or brush. It is also safe to use an ultrasonic cleaner, though steam cleaning should be avoided. Sardonyx should be stored in a dry place to prevent any potential damage from moisture.
Spinel
Spinel is a durable gemstone with a hardness of 8 on the Mohs scale, making it suitable for everyday wear. It can be cleaned with a mild soap solution and a soft cloth or brush. Spinel is also safe to use with ultrasonic and steam cleaners. It should be stored in a dry place away from other gemstones to prevent scratches.
Conclusion
The August birthstones—peridot, sardonyx, and spinel—offer a unique combination of color, symbolism, and history. From the vibrant green of peridot to the bold striped patterns of sardonyx and the sparkling diversity of spinel, each gemstone contributes its own distinct character to the August birthstone tradition.
These gemstones have been cherished for centuries for their beauty, durability, and symbolic meanings. Whether used in jewelry, as protective amulets, or as decorative pieces, they continue to captivate gemstone enthusiasts and jewelry buyers alike. Understanding their geological properties, historical significance, and symbolic meanings provides a deeper appreciation for these remarkable stones.
As a birthstone, each of these gems carries a special meaning for those born in August, offering not only beauty but also a sense of connection to history and tradition. Whether worn for their aesthetic appeal or their symbolic significance, peridot, sardonyx, and spinel continue to shine as the enduring birthstones of August.