August is one of the few months in the birthstone calendar to be represented by three distinct gemstones: peridot, spinel, and sardonyx. Each of these stones carries its own rich history, unique gemological properties, and symbolic meanings. Whether you're drawn to the vibrant green of peridot, the fiery red of spinel, or the striking striped bands of sardonyx, August birthstones offer a diverse and meaningful selection. This article explores the characteristics, historical significance, and cultural importance of these three gems, offering a comprehensive overview for gemstone enthusiasts, jewelry collectors, and those curious about the symbolic power of stones.
History and Lore
The history of the August birthstones is a fascinating tapestry that spans ancient civilizations, medieval superstitions, and modern recognition by gemological institutions.
Peridot: The "Sun Gem"
Peridot, often referred to as the "sun gem," has been cherished for millennia. The ancient Egyptians called it the "gem of the sun" and believed it could ward off nightmares and evil spirits. Some even claimed that Cleopatra’s famed emerald collection was actually composed of peridot. These misconceptions were common, as peridot can resemble emerald under artificial light, giving it the nickname "evening emerald."
Peridot was found on the island of Topazios in the Red Sea, where it was once mistakenly associated with topaz. This island was a significant source of peridot in antiquity. The stone has also been discovered in meteorites, making it one of the few gemstones that originate in outer space. These extraterrestrial peridot specimens are known as Pallasite Meteorites and are too small for jewelry use, but they contribute to the stone’s unique mystique.
Peridot was highly valued in medieval Europe as well, particularly by the Vikings, who believed it could protect them from witchcraft and curses. The stone has also been found in archaeological sites across the Middle East and Africa, suggesting its widespread use and cultural significance.
Sardonyx: The Ancient Stone of Strength
Sardonyx has the longest historical lineage among the August birthstones. It has been used for over 4,000 years and was particularly popular in ancient Egypt, Greece, and Rome. Sardonyx is a banded variety of chalcedony, combining sard (a reddish-brown quartz) and onyx (a white or black quartz). Its bold stripes made it a favorite for cameos and seals, which were used for engraving and marking documents or wax.
The stone was believed to bring courage and strength to warriors and leaders. Roman soldiers wore sardonyx amulets for protection in battle. In medieval Europe, it was thought to enhance self-control and provide clarity in decision-making.
Spinel: The Underrated Sparkler
Spinel is the youngest of the three August birthstones to be officially recognized. It was only added to the list in 2016 by the American Gem Trade Association (AGTA). This relatively recent recognition is due in part to the stone’s frequent misidentification with ruby and other red gemstones in earlier centuries.
Spinel has been found in ancient royal collections and was even featured in the British Crown Jewels before its true identity was known. In Burma (Myanmar), spinel was mined for centuries, and some of the finest specimens were traded along the Silk Road. Today, spinel is gaining popularity for its brilliant colors and affordability compared to rubies and other red gemstones.
Geological Formation and Sources
Understanding the geological origins of a gemstone provides insight into its rarity, beauty, and value. Each of the August birthstones forms under unique conditions and is found in specific regions around the world.
Peridot: Formed in Fire
Peridot is a silicate mineral that forms in the Earth's mantle and is brought to the surface through volcanic activity. It is commonly found in lava flows and volcanic rocks, where it crystallizes from magma. The presence of iron in peridot is what gives it its signature green color. The more iron present, the deeper the green.
Peridot is also found in meteorites, which are fragments of asteroids that have fallen to Earth. These extraterrestrial sources are of great scientific interest, though they rarely produce gem-quality stones suitable for jewelry.
Commercial peridot is primarily sourced from:
- Arizona, USA: Known for its high-quality, bright green peridot.
- Pakistan and China: Also significant sources, where peridot is often mined in volcanic regions.
- Madagascar, Myanmar, and Brazil: Emerging sources in recent years.
Sardonyx: A Product of Time and Pressure
Sardonyx is a type of chalcedony, which is a cryptocrystalline form of quartz. It forms in the cavities of volcanic rocks, where mineral-rich water deposits layers of silica over time. The alternating bands of sard and onyx give sardonyx its distinctive striped appearance.
Historically, sardonyx was mined in:
- Turkey and the Middle East: Ancient sources that were used by the Egyptians and Greeks.
- India: A major historical source for sardonyx, especially in the state of Rajasthan.
- Brazil and the United States: Modern sources, with Brazil producing some of the finest banded material.
Spinel: The Versatile Gem
Spinel forms in a variety of geological settings, including metamorphic and igneous rocks. It is often found in the same deposits as ruby and garnet, which can lead to confusion. Spinel comes in a wide range of colors, from deep red to vivid blue, pink, orange, and even black.
The primary sources of spinel include:
- Myanmar (Burma): Known for producing some of the finest red spinel.
- Sri Lanka: A significant source of blue and pink spinel.
- Vietnam and Afghanistan: Emerging sources of high-quality spinel.
- Brazil and Madagascar: Also producing notable quantities, particularly in pink and orange tones.
Gemological Properties
Each of the August birthstones has distinct physical and chemical properties that make them unique in the world of gemology.
Peridot
- Chemical Formula: (Mg,Fe)₂SiO₄
- Crystal System: Orthorhombic
- Hardness (Mohs Scale): 6.5 to 7
- Refractive Index: 1.650 to 1.690
- Color: Green, ranging from light yellow-green to deep olive green
- Luster: Vitreous (glassy)
- Inclusions: Common, often visible as small crystals or "horsetail" inclusions
- Transparency: Transparent to translucent
Peridot is relatively soft compared to other gemstones, so it can be prone to scratches. It also has a perfect cleavage, meaning it can be split along certain planes if struck with enough force.
Sardonyx
- Chemical Formula: SiO₂ (silicon dioxide)
- Crystal System: Trigonal (as part of the quartz family)
- Hardness (Mohs Scale): 6.5 to 7
- Refractive Index: 1.486 to 1.530
- Color: Reddish-brown and white bands
- Luster: Waxy to vitreous
- Transparency: Translucent
- Inclusions: Rare; generally free of visible inclusions
Sardonyx is durable and easy to care for, making it a popular choice for engraved jewelry and decorative objects. Its hardness and resilience make it suitable for everyday wear.
Spinel
- Chemical Formula: MgAl₂O₄ (for red spinel); varies with color
- Crystal System: Isometric (cubic)
- Hardness (Mohs Scale): 8
- Refractive Index: 1.718 to 1.755
- Color: Red, pink, orange, blue, purple, black, and more
- Luster: Vitreous
- Transparency: Transparent
- Inclusions: Rare; most spinel is eye-clean
Spinel is one of the hardest of the August birthstones, with a hardness comparable to that of corundum (rubies and sapphires). This makes it highly durable and suitable for a wide range of jewelry settings.
Below is a table summarizing the key gemological properties of the August birthstones:
| Property | Peridot | Sardonyx | Spinel |
|---|---|---|---|
| Chemical Formula | (Mg,Fe)₂SiO₄ | SiO₂ | MgAl₂O₄ (for red spinel) |
| Crystal System | Orthorhombic | Trigonal | Isometric |
| Hardness (Mohs) | 6.5–7 | 6.5–7 | 8 |
| Refractive Index | 1.650–1.690 | 1.486–1.530 | 1.718–1.755 |
| Color | Green (yellow-green to olive) | Reddish-brown and white bands | Red, pink, blue, orange, black, etc. |
| Luster | Vitreous | Waxy to vitreous | Vitreous |
| Inclusions | Common | Rare | Rare |
| Transparency | Transparent to translucent | Translucent | Transparent |
| Cleavage | Perfect cleavage | None | None |
Symbolism and Metaphysical Beliefs
Each of the August birthstones carries its own set of symbolic meanings and metaphysical properties, which have been passed down through history and continue to be relevant in modern times.
Peridot: Prosperity, Protection, and Peace
Peridot is often associated with positivity, prosperity, and protection. It is believed to promote calmness, reduce stress, and encourage emotional healing. In ancient times, peridot was used to ward off nightmares and negative energy. Some cultures believed that keeping peridot near one's bed could prevent bad dreams and promote restful sleep.
The stone is also a symbol of friendship and harmony. It is said to enhance communication and understanding between people, making it a popular choice for couples and close friends. In addition, peridot is associated with the sun, symbolizing warmth, light, and vitality.
Sardonyx: Courage, Strength, and Clarity
Sardonyx is known as a stone of strength and courage. It is believed to help individuals face challenges with confidence and resolve. In ancient times, warriors and leaders wore sardonyx to gain protection and clarity in decision-making. It was also used in religious and spiritual practices to enhance focus and willpower.
Sardonyx is also associated with self-control and discipline. It is thought to help individuals manage their emotions and avoid impulsive behavior. This makes it a popular stone for those seeking stability and balance in their lives.
Spinel: Vitality, Passion, and Transformation
Spinel is a stone of vitality and energy. It is believed to stimulate passion, creativity, and motivation. Red and pink spinel, in particular, are associated with love and romance, making them popular choices for engagement rings and anniversary gifts.
Spinel is also considered a stone of transformation. It is thought to help individuals let go of the past and embrace new beginnings. This makes it a powerful tool for those undergoing personal change or seeking to move forward with confidence.
Care and Cleaning
Proper care and cleaning are essential to preserving the beauty and longevity of gemstones. The care instructions for each August birthstone depend on its hardness, chemical composition, and sensitivity to heat and light.
Peridot
Peridot is relatively soft and has perfect cleavage, so it should be handled with care. It can be damaged by sharp blows or sudden temperature changes.
- Cleaning: Gently clean peridot with warm, soapy water and a soft cloth. Avoid using steam cleaners or ultrasonic cleaners, as these can damage the stone.
- Storage: Store peridot separately from harder gemstones to prevent scratches. Wrap it in a soft cloth or store it in a padded jewelry box.
Sardonyx
Sardonyx is more durable than peridot, with a hardness of 6.5 to 7. It is also resistant to most chemicals and heat.
- Cleaning: Sardonyx can be cleaned with warm, soapy water and a soft cloth. It can also be safely cleaned with steam or ultrasonic cleaners.
- Storage: Sardonyx can be stored with other gemstones, but it's best to keep it in a dry place to prevent any potential moisture damage.
Spinel
Spinel is one of the hardest of the August birthstones, making it highly durable and suitable for everyday wear.
- Cleaning: Spinel can be cleaned with warm, soapy water, steam, or ultrasonic cleaners. It is also resistant to most chemicals.
- Storage: Spinel can be stored with other gemstones, but it should be kept away from abrasive materials to avoid scratches.
Conclusion
The August birthstones—peridot, spinel, and sardonyx—each offer a unique blend of beauty, history, and symbolism. Whether you're drawn to the vibrant green of peridot, the fiery red of spinel, or the bold banded appearance of sardonyx, these stones are rich in meaning and significance.
Peridot, with its ancient associations with the sun and protection, continues to be a beloved gemstone for those born in August. Sardonyx, with its long history of use in ancient civilizations, offers strength and clarity. Spinel, though newly recognized as an official August birthstone, is gaining popularity for its brilliant colors and durability.
Each of these stones carries its own unique story, making them not just beautiful adornments, but also meaningful symbols of identity, heritage, and personal power. Whether you choose one or all three, the August birthstones are a testament to the enduring allure of gemstones and their ability to connect us to history, culture, and the natural world.