August is a month of vibrant energy, marked by meteor showers, the return to school, and the peak of summer in the Northern Hemisphere. It is also a month rich in gemstone lore, with three officially recognized birthstones: peridot, sardonyx, and spinel. This triad of gemstones offers a remarkable diversity of colors, histories, and symbolic meanings, making August one of the most unique and historically significant months in the birthstone tradition.
This article delves into the geological properties, historical background, cultural symbolism, and care instructions for each of these three August birthstones. Drawing from authoritative sources and scholarly references, we explore how these gemstones have been revered across cultures and eras, and how they continue to captivate gemstone enthusiasts and jewelry buyers today.
History and Lore
August’s birthstone tradition is one of the most diverse in the calendar year, with nine different gemstones having been associated with the month at different points in history. The modern list, however, recognizes three official August birthstones: peridot, sardonyx, and spinel.
Sardonyx: The Ancient August Birthstone
Sardonyx holds the distinction of being the oldest recorded birthstone for August. Its history dates back over 4,000 years, and it is referenced in biblical texts as one of the foundation stones of the city of Jerusalem and as part of the high priest’s breastplate. The gemstone is a variety of onyx, characterized by its alternating bands of red-brown (sard) and white (onyx), sometimes with additional hues such as black, brown, or gray.
Sardonyx was traditionally used as a protective stone, believed to enhance confidence, optimism, and joy. It was also considered a stone of strength and vitality, particularly in ancient Hebrew traditions. As the original August birthstone, sardonyx remained in use until the early 20th century when peridot was officially adopted as a modern birthstone.
Peridot: The Green Jewel of the Ancients
Peridot, known for its vivid green color, was added as a modern birthstone in the early 20th century. It is now the most widely recognized of the August birthstones, often associated with good fortune, emotional well-being, and the ability to reduce stress. Peridot is a variety of the mineral olivine, and its color is due to the presence of iron.
Interestingly, peridot has a long and sometimes confusing history. It has been mistaken for other gemstones such as topaz, emerald, and even ruby. For example, the Shrine of the Three Holy Kings in Cologne Cathedral was believed to be adorned with emeralds, but in fact, the gems were peridots. Similarly, some historians speculate that Cleopatra’s famous emerald collection may have been composed of peridots.
The confusion between peridot and topaz is also rooted in the gemstone’s historical origins. The Red Sea island of Topazios, from which the name “topaz” is derived, actually produced peridot, not topaz. This has led to centuries of misidentification, with peridot being referred to as “topaz” by ancient scholars such as Pliny the Elder.
Peridot is also the only gemstone formed in the Earth’s mantle, brought to the surface through volcanic activity. Some peridot crystals have even been found in meteorites, making them truly cosmic in origin.
Spinel: The Modern Addition to August
Spinel was officially added to the August birthstone list in 2016, a rare and significant update to the traditional birthstone calendar. The decision was made by the Jewelers of America (JA) and the American Gem Trade Association (AGTA), recognizing spinel’s beauty, rarity, and historical significance.
Spinel comes in a wide range of colors, but the most popular variety for August is the vibrant pink or ruby-red hue. It is often confused with ruby, as both share a similar red color. In fact, many historical “rubies” were later identified as spinel. Spinel is a durable gemstone, with a hardness of 8 on the Mohs scale, making it suitable for everyday wear.
The addition of spinel to the August birthstone list reflects a growing appreciation for gemstones that offer both aesthetic appeal and affordability, while still maintaining a rich historical legacy.
Geological Formation and Sources
Each of the August birthstones has a unique geological profile and origin story, shaped by the natural processes that formed them.
Peridot
Peridot is a silicate mineral, chemically classified as a member of the olivine group. Its chemical formula is (Mg,Fe)₂SiO₄, with the color variation depending on the ratio of magnesium to iron. Peridot is known for its vivid green color, ranging from yellow-green to olive green.
The most notable feature of peridot is its cosmic origin. It is one of the few gemstones formed in the Earth’s mantle, carried to the surface through volcanic activity. Peridot can also be found in meteorites, particularly those of the chondrite type. The presence of peridot in meteorites is a testament to its extraterrestrial origins and makes it one of the few gemstones with a truly interstellar connection.
Major sources of peridot include the United States (especially in Arizona and Nevada), Myanmar (Burma), China, and Brazil. The American Southwest, in particular, has become a significant source of high-quality peridot due to recent discoveries.
Sardonyx
Sardonyx is a type of chalcedony, a microcrystalline form of quartz. It is composed of alternating bands of sard (a reddish-brown variety of onyx) and onyx (a white or pale-colored variety). These bands can be straight, curved, or even wavy, depending on the geological conditions under which the stone formed.
Sardonyx is typically found in sedimentary rocks, often in the form of nodules or veins. The red-brown color is due to the presence of iron oxides, while the white or pale color is due to the pure quartz content.
Historically, sardonyx was mined in regions such as India, Egypt, and the Middle East. Today, major sources include Brazil, India, and the United States. The stone is relatively easy to carve, which has contributed to its popularity in jewelry and ornamental objects.
Spinel
Spinel is a mineral composed of magnesium aluminum silicate, with the chemical formula MgAl₂O₄. It occurs in a wide range of colors, including red, pink, blue, purple, and even colorless. The most valuable and sought-after spinel is the deep red or pink variety, which is often mistaken for ruby.
Spinel is formed in metamorphic and igneous rocks, particularly in areas where there is a high concentration of aluminum and magnesium. It is found in a variety of geological settings, including marble, gneiss, and basalt.
Historical sources of spinel include Burma (Myanmar), Sri Lanka, and Afghanistan. However, recent discoveries in Madagascar and Vietnam have expanded the availability of high-quality spinel. The gemstone is relatively durable, with a hardness of 8 on the Mohs scale, making it suitable for use in rings, pendants, and other jewelry pieces.
Gemological Properties
Understanding the gemological properties of peridot, sardonyx, and spinel is essential for both collectors and jewelry buyers. Each of these gemstones has distinct characteristics that influence their appearance, durability, and value.
Peridot
- Chemical Composition: (Mg,Fe)₂SiO₄
- Color: Yellow-green to olive green
- Hardness: 6.5–7 on the Mohs scale
- Refractive Index: 1.65–1.70
- Luster: Vitreous
- Transparency: Transparent to translucent
- Inclusions: Common, often visible as small inclusions or “needles”
- Cleavage: Poor
- Origin of Color: Iron content
Peridot is a relatively soft gemstone, which makes it susceptible to scratches and chips. It is best suited for jewelry that is not worn daily, such as earrings or pendants. Its inclusions are often considered part of its character and charm, rather than flaws.
Sardonyx
- Chemical Composition: Silica (SiO₂)
- Color: Alternating bands of sard (reddish-brown) and onyx (white or pale)
- Hardness: 6.5–7 on the Mohs scale
- Refractive Index: 1.48–1.53
- Luster: Waxy to subvitreous
- Transparency: Translucent to opaque
- Inclusions: Rare, due to its opaque nature
- Cleavage: None
- Origin of Color: Iron oxides (sard) and pure quartz (onyx)
Sardonyx is a durable gemstone, with a hardness similar to that of peridot. Its opaque nature makes it less prone to damage, and it is often used in carved cameos, seals, and ornamental pieces. It is also a popular choice for rings and bracelets.
Spinel
- Chemical Composition: MgAl₂O₄
- Color: Red, pink, blue, purple, and more
- Hardness: 8 on the Mohs scale
- Refractive Index: 1.718–1.759
- Luster: Vitreous
- Transparency: Transparent to translucent
- Inclusions: Varies, but generally fewer than in peridot
- Cleavage: None
- Origin of Color: Chromium (red) and cobalt (blue)
Spinel is one of the hardest of the August birthstones, making it ideal for use in rings and other jewelry that is worn frequently. Its refractive index is higher than that of peridot and sardonyx, giving it a brilliant, fiery luster. Spinel is also relatively rare, which contributes to its value and appeal.
Symbolism and Metaphysical Beliefs
The August birthstones have long been associated with a range of symbolic and metaphysical properties, rooted in ancient traditions and cultural beliefs.
Peridot
Peridot is considered a stone of warmth, friendliness, and good fortune. It is believed to bring positive energy, reduce stress, and foster emotional well-being. In ancient times, it was used as a protective stone, helping to ward off nightmares and negative influences.
Peridot is also associated with personal responsibility and forgiveness. It is said to help individuals take ownership of their actions and learn from their mistakes. This makes it particularly valuable for those who struggle with self-forgiveness or holding themselves accountable.
In addition, peridot is believed to support creativity and willpower. It is a popular stone for artists, writers, and other creative professionals, as it is thought to enhance imagination and self-expression.
Sardonyx
Sardonyx is a stone of protection, confidence, and optimism. It is often used to enhance one’s courage and resilience, particularly in times of uncertainty or challenge. In ancient cultures, it was considered a powerful talisman, believed to shield the wearer from harm and negative energies.
Sardonyx is also associated with emotional balance and stability. It is said to help individuals stay grounded and focused, especially in high-pressure situations. This makes it a popular choice for those in leadership roles or those who need to make important decisions.
The stone is also believed to enhance communication and self-expression, helping individuals articulate their thoughts and emotions more clearly. It is a valuable tool for those who struggle with social anxiety or difficulty expressing themselves.
Spinel
Spinel is a stone of passion, vitality, and emotional healing. It is believed to enhance confidence, courage, and self-esteem, making it particularly beneficial for individuals who struggle with self-doubt or low self-worth.
Spinel is also associated with love and romance. It is believed to strengthen relationships and deepen emotional connections. It is a popular stone for couples and those seeking to improve their romantic lives.
In addition, spinel is thought to promote emotional balance and resilience. It is said to help individuals release negative emotions and move forward with a sense of clarity and purpose.
Care and Cleaning
Proper care and maintenance are essential for preserving the beauty and longevity of any gemstone. Here are some guidelines for caring for peridot, sardonyx, and spinel:
Peridot
- Hardness: 6.5–7 (relatively soft)
- Cleavage: Poor
- Cleaning: Use a soft cloth and mild soap with lukewarm water. Avoid ultrasonic cleaners and steamers, as they can damage the stone.
- Storage: Store peridot separately from harder gemstones to prevent scratches.
- Avoid: Exposure to harsh chemicals, extreme heat, or sudden temperature changes.
Due to its relative softness, peridot is best suited for jewelry that is not worn daily. Rings and bracelets should be worn with care, and any pieces with peridot should be inspected regularly for signs of wear or damage.
Sardonyx
- Hardness: 6.5–7
- Cleavage: None
- Cleaning: Sardonyx can be cleaned with a soft cloth and mild soap. It is generally more durable than peridot, but still requires gentle handling.
- Storage: Store sardonyx in a dry, cool place to prevent damage from humidity or temperature fluctuations.
- Avoid: Exposure to harsh chemicals or abrasive cleaners.
Sardonyx is a more durable gemstone than peridot and can be worn more frequently. However, it should still be handled with care, especially in rings and bracelets where it is more likely to be subjected to wear and tear.
Spinel
- Hardness: 8 (very durable)
- Cleavage: None
- Cleaning: Spinel can be cleaned with a soft cloth and mild soap. It is also safe to use ultrasonic cleaners and steamers.
- Storage: Store spinel in a dry, cool place. It is generally more resistant to damage than peridot or sardonyx.
- Avoid: Exposure to harsh chemicals or abrasive cleaners.
Spinel is one of the most durable of the August birthstones, making it an excellent choice for everyday wear. It is safe to use in rings, pendants, and other jewelry pieces that are worn regularly.
Conclusion
The August birthstones—peridot, sardonyx, and spinel—represent a rich tapestry of geological, historical, and cultural significance. From the ancient sardonyx of biblical times to the vibrant peridot of volcanic origin, and the modern addition of spinel, each of these gemstones carries a unique legacy and symbolism.
Whether you are drawn to the calming green of peridot, the earthy bands of sardonyx, or the passionate hues of spinel, these stones offer a meaningful connection to both the past and the present. As gemstone enthusiasts, jewelry buyers, and students of gemology, we can appreciate not only their beauty but also the stories they carry.
In the world of birthstones, August stands out as a month of diversity and depth, offering a choice that reflects individual style, cultural heritage, and personal meaning.