The month of August is uniquely blessed with three official birthstones: Peridot, Spinel, and Sardonyx. This selection reflects a rich tapestry of geological diversity and cultural heritage. Each gemstone carries its own distinct history, symbolism, and physical properties, making August one of only three months—alongside June and December—to be associated with more than one birthstone. Among these, Peridot and Spinel are recognized as the modern August birthstones, while Sardonyx is considered an alternative or traditional choice. Additionally, both Peridot and Sapphire are zodiac birthstones for August, with Peridot representing the Leo zodiac sign and Sapphire representing Virgo.
This article delves into the geological and historical background of these gemstones, their symbolic meanings, and their relevance in both ancient and modern contexts. It also explores how these stones are connected to the zodiac signs associated with August and provides guidance on their care and usage in jewelry. The discussion is grounded in the information provided by authoritative and widely referenced sources, ensuring accuracy and depth in understanding.
History and Lore
The concept of assigning gemstones to specific months of the year has ancient roots. Early astrologers believed that gemstones possessed the power to influence or protect individuals depending on the time of their birth. The modern list of birthstones was first formalized in 1912 by the American National Association of Jewelers, which was later succeeded by the American Gem Trade Association (AGTA) and the Jewelers of America (JA). In 2016, these organizations updated the list to include additional gemstones for certain months, including August, which now includes Peridot, Spinel, and Sardonyx.
Peridot, the most prominent of the August birthstones, has been known for thousands of years. It was often mistaken for emerald in ancient times due to its green color. However, Peridot is distinct in its composition and properties. The gemstone has been found in meteorites and volcanic lava, contributing to its mystique and allure. In ancient Egypt, Peridot was called the "gem of the sun" and was used in jewelry and religious artifacts.
Spinel, while less well-known than Peridot, has a long history of being mistaken for ruby due to its vibrant red and pink hues. It was only in the 18th and 19th centuries that Spinel was correctly identified as a separate gemstone. Its inclusion as an August birthstone in 2016 marks a recognition of its beauty and versatility across a range of colors including red, blue, pink, and purple.
Sardonyx, the traditional birthstone for August, is a banded chalcedony with layers of red and white. It was popular in ancient Rome and was often used in signet rings for sealing wax and official documents. The stone’s durability and clarity made it a favored choice for engraving, and it was believed to bring courage and protection to its wearer.
The inclusion of multiple birthstones for August reflects the diversity and richness of gemstone history and use. It also underscores the evolving nature of birthstone traditions, which continue to adapt to new discoveries and changing cultural values.
Geological Formation and Sources
Each of the August birthstones forms under different geological conditions, resulting in distinct characteristics and sources.
Peridot
Peridot is a silicate mineral with the chemical formula (Mg,Fe)₂SiO₄. It is primarily found in the Earth's upper mantle, where it is brought to the surface through volcanic activity. Peridot can also be found in meteorites, particularly in a type known as pallasite meteorites, which contain large, well-formed crystals of olivine. However, these meteorite-derived peridots are typically too small for jewelry use.
The finest peridot is sourced from deposits in Egypt, Burma (Myanmar), and the United States. Egyptian peridot, known for its intense green color, was historically mined from the Isle of Zabargad in the Red Sea. Burmese peridot is also highly prized, while American deposits, particularly in Arizona, have provided significant quantities of high-quality material.
Peridot is relatively soft compared to other gemstones, with a hardness of 6.5 to 7 on the Mohs scale. This makes it suitable for jewelry, though it requires careful handling to avoid scratches and damage.
Spinel
Spinel is a mineral composed of magnesium aluminum silicate, with the chemical formula MgAl₂O₄. It forms in a variety of colors, including red, pink, blue, purple, and even colorless, depending on the trace elements present. Red and pink spinels owe their color to the presence of chromium or iron, while blue spinels are colored by cobalt.
Spinel is typically found in metamorphic and igneous rocks, and some of the finest specimens have been discovered in Burma, Afghanistan, and Sri Lanka. The gemstone was historically confused with ruby and sapphire due to its similar appearance and was often used in royal jewelry collections.
Spinel has a hardness of 8 on the Mohs scale, making it more durable than peridot and suitable for everyday wear in jewelry. It is also relatively stable and resistant to heat and chemicals, which makes it easy to clean and maintain.
Sardonyx
Sardonyx is a type of chalcedony, a form of quartz composed of silicon dioxide (SiO₂). It is characterized by its banded pattern of red and white, with the red portions derived from iron oxide and the white from pure quartz. The term "sardonyx" comes from the Greek words sardis (a type of red jasper) and onyx (a type of banded chalcedony).
Sardonyx forms in sedimentary rocks and is commonly found in deposits in India, Brazil, and the United States. It was particularly popular in ancient Rome, where it was used to make signet rings for official use and personal adornment.
Sardonyx has a hardness of 6.5 to 7 on the Mohs scale, making it durable enough for jewelry use, though it is more susceptible to damage than spinel. Its layered structure can also make it prone to chipping if struck from the side.
Gemological Properties
Understanding the gemological properties of each August birthstone is essential for both gemologists and jewelry buyers. These properties determine how the stones are cut, set, and cared for, as well as their durability and visual appeal.
Peridot
- Chemical Formula: (Mg,Fe)₂SiO₄
- Hardness: 6.5–7 on the Mohs scale
- Refractive Index: 1.65–1.69
- Color: Green, ranging from yellow-green to deep olive green
- Luster: Vitreous (glassy)
- Transparency: Transparent to translucent
- Inclusions: Common; often visible as small crystals or fractures
- Cleavage: Perfect in one direction
- Specific Gravity: 3.30–3.45
- Origin: Egypt, Myanmar, United States
Peridot’s color is due to the presence of iron in its crystal structure. The higher the iron content, the deeper the green. It is often cut in a round brilliant or cushion style to enhance its brilliance and fire. Due to its perfect cleavage and moderate hardness, peridot should be set in secure settings and handled with care to avoid damage.
Spinel
- Chemical Formula: MgAl₂O₄
- Hardness: 8 on the Mohs scale
- Refractive Index: 1.718–1.722
- Color: Red, pink, blue, purple, colorless
- Luster: Vitreous
- Transparency: Transparent
- Inclusions: Rare; usually clean and clear
- Cleavage: None
- Specific Gravity: 3.60–4.00
- Origin: Myanmar, Afghanistan, Sri Lanka
Spinel is highly durable and resistant to scratches and abrasion. Its refractive index is slightly higher than that of corundum (rubies and sapphires), giving it a lively and brilliant appearance. Spinel is often cut in a round brilliant or princess cut to maximize its fire and brilliance. Because of its hardness and lack of cleavage, it is well suited for everyday wear in rings and pendants.
Sardonyx
- Chemical Formula: SiO₂ (silica)
- Hardness: 6.5–7 on the Mohs scale
- Refractive Index: 1.48–1.53
- Color: Banded red and white
- Luster: Waxy to vitreous
- Transparency: Translucent to opaque
- Inclusions: Rare
- Cleavage: None
- Specific Gravity: 2.60–2.65
- Origin: India, Brazil, United States
Sardonyx is a durable and stable gemstone with a smooth, waxy luster. It is often cut in cabochon or carved designs to showcase its banding. Because of its hardness and lack of cleavage, it is suitable for use in rings, pendants, and earrings. However, due to its layered structure, it should be handled with care to prevent chipping.
Symbolism and Metaphysical Beliefs
Each of the August birthstones has been associated with various symbolic and metaphysical properties across different cultures and time periods.
Peridot
Peridot has long been regarded as a stone of renewal and rejuvenation. In ancient Egypt, it was believed to bring protection and prosperity to its wearer. It was also thought to have the power to ward off nightmares and negative energies. In medieval Europe, peridot was used in religious jewelry and was believed to enhance spiritual clarity and divine insight.
Modern metaphysical beliefs attribute peridot with properties of emotional healing and balance. It is considered a stone of transformation, helping individuals let go of the past and embrace new beginnings. Peridot is also associated with the heart chakra and is believed to promote love, loyalty, and emotional stability.
Spinel
Spinel has been regarded as a stone of strength and vitality. In ancient times, it was believed to bring courage and protection to warriors and leaders. It was also used in royal jewelry and was associated with power and authority.
In modern metaphysical traditions, spinel is considered a stone of motivation and inspiration. It is believed to enhance one’s ability to take action and pursue goals with confidence and determination. Spinel is also associated with the sacral chakra and is believed to support emotional balance and creativity.
Sardonyx
Sardonyx has been historically associated with courage, protection, and self-control. In ancient Rome, it was used in signet rings for official purposes and was believed to bring authority and protection to the wearer. It was also used in amulets and talismans to ward off negative influences and promote mental clarity.
Modern metaphysical beliefs attribute sardonyx with properties of grounding and emotional stability. It is believed to help individuals maintain a sense of balance and composure, even in challenging situations. Sardonyx is also associated with the root chakra and is believed to support a strong connection to the earth and a sense of security.
Care and Cleaning
Proper care and maintenance are essential to preserving the beauty and longevity of August birthstone jewelry. Each gemstone has specific care requirements based on its physical properties and susceptibility to damage.
Peridot
- Cleaning: Use warm, soapy water and a soft cloth to clean peridot. Avoid using harsh chemicals or steam cleaning, as these can damage the stone.
- Storage: Store peridot separately from harder gemstones to prevent scratches. Wrap it in a soft cloth or place it in a fabric-lined jewelry box.
- Handling: Avoid exposing peridot to sudden temperature changes or excessive force, as it can be prone to chipping due to its perfect cleavage.
Spinel
- Cleaning: Spinel can be cleaned using warm, soapy water and a soft cloth. Ultrasonic and steam cleaning are also safe methods for cleaning spinel.
- Storage: Store spinel in a dry place, away from abrasive materials. It can be stored with other gemstones due to its high hardness.
- Handling: Spinel is durable and resistant to scratches and abrasion. However, it should still be handled with care to avoid accidental damage.
Sardonyx
- Cleaning: Sardonyx can be cleaned using warm, soapy water and a soft cloth. Avoid using harsh chemicals or abrasive cleaners, as these can dull its surface.
- Storage: Store sardonyx separately from harder gemstones to prevent scratches. It can also be wrapped in a soft cloth for added protection.
- Handling: Sardonyx is relatively durable, but its layered structure makes it susceptible to chipping if struck from the side. Handle it with care to avoid damage.
Conclusion
August is a month rich in gemstone heritage, with three distinct birthstones—Peridot, Spinel, and Sardonyx—each offering unique beauty, symbolism, and geological significance. Peridot, the most prominent of these, has been cherished for centuries for its vibrant green color and protective properties. Spinel, with its dazzling range of colors, adds versatility and brilliance to the list, while Sardonyx, with its banded red and white pattern, brings a sense of tradition and stability.
These gemstones are not only valuable for their aesthetic appeal but also for the rich cultural and historical meanings they carry. Whether used in jewelry or kept as collectibles, they serve as enduring symbols of personal connection, protection, and transformation. Understanding their properties, history, and care requirements allows for a deeper appreciation of these remarkable stones and ensures their continued beauty for generations to come.