The month of August is uniquely blessed in the world of gemstones, as it is associated with three official birthstones: peridot, sardonyx, and spinel. These stones offer a wide range of colors, meanings, and historical significance, making August one of the most diverse and rich months in the birthstone calendar. Each of these gems has its own unique charm and properties, and together they represent the warmth, energy, and depth of summer.
This article explores the scientific properties, historical significance, cultural symbolism, and practical care of these August birthstones. Whether you're an August-born individual looking to celebrate your month, a gemstone enthusiast, or a jewelry buyer, this in-depth guide will provide you with a comprehensive understanding of the August birthstones.
History and Lore
The history of the August birthstones is as rich and varied as the stones themselves. While peridot is considered the primary and most recognized of the three, both sardonyx and spinel have played significant roles in different cultures and eras.
Peridot: The Ancient “Evening Emerald”
Peridot has been treasured for thousands of years, with its earliest recorded use dating back to the ancient Egyptians, who called it the “Evening Emerald.” This name was given due to its striking green color, which was especially luminous under candlelight or moonlight. Egyptian pharaohs prized peridot for its protective qualities and often set it in gold to wear as talismans.
The Romans, too, valued peridot and believed it brought happiness and strength. They mistakenly thought that all green gems were either emeralds or peridots, and some of the finest peridots were once thought to be emeralds brought from the East.
Peridot has also been found in volcanic lava flows, where it is formed deep within the Earth’s mantle and brought to the surface by volcanic activity. Some of the most beautiful peridots are found in pumice deposits, such as those on the island of Zabargad (St. John’s Island), located in the Red Sea.
Sardonyx: The Stone of Ancient Strength
Sardonyx has a long and storied history, with its use dating back to ancient Greece and Rome. The name “sardonyx” is derived from the Sardinian region, where it was first discovered, and the Greek word “onyx,” referring to the stone’s banded appearance.
Sardonyx is a banded variety of chalcedony, typically featuring reddish-brown bands over a white or light brown background. The Romans believed that sardonyx could ward off envy and strengthen the will, making it a popular stone for warriors and leaders. It was often carved into cameos and intaglios for rings and seals, a practice that continued through the Renaissance and into modern times.
In medieval Europe, sardonyx was used as a protective charm, especially for travelers and those in positions of power. It was thought to promote courage, stability, and clear thinking.
Spinel: A Royal Gem with a Late Recognition
Spinel is the most recently recognized of the three August birthstones, having been officially added in 2016 by the American Gem Trade Association (AGTA). Before this, spinel was often mistaken for ruby or garnet due to its similar appearance and color.
Spinel has a long royal history, with some of the most famous historical gems being spinels. For example, the “Black Prince’s Ruby”, set in the British Imperial State Crown, is actually a large red spinel. For centuries, spinel was valued for its brilliance and fire, and it was often used in royal jewelry and regalia.
Spinel comes in a wide range of colors, including red, pink, orange, blue, and even black. The red and pink varieties are the most popular in August birthstone jewelry, offering a sparkling and vibrant alternative to traditional red gemstones like ruby.
Geological Formation and Sources
Each of the August birthstones has a unique geological origin, and understanding these processes helps appreciate the rarity and beauty of each gem.
Peridot: A Gem from the Earth’s Mantle
Peridot is a silicate mineral with the chemical formula Mg₂SiO₄, and it forms in magnesium-rich volcanic rocks. It is one of the few gemstones that can be found in meteorites, and it is believed that some of the finest peridots have extraterrestrial origins.
The most important sources of high-quality peridot include:
- Zabargad Island (Red Sea): Known for its large, vivid green peridots.
- Arizona, USA: A major source of peridot in the United States.
- Mali, Pakistan, and Myanmar: Other significant sources of the gemstone.
Peridot is relatively hard and durable, with a Mohs hardness of 6.5 to 7, making it suitable for everyday jewelry. It is also relatively affordable compared to other colored gemstones of similar size and brilliance.
Sardonyx: A Banded Chalcedony with Ancient Roots
Sardonyx is a microcrystalline variety of quartz, composed of silica (SiO₂) with small amounts of iron oxides, which give it its reddish and brownish bands. It is formed through the slow deposition of silica-rich water, which solidifies over time to form banded patterns.
Key sources of sardonyx include:
- Sardinia, Italy: The historical source from which the stone gets its name.
- India, Brazil, and the United States: Modern sources that provide large quantities of high-quality material.
Sardonyx is relatively soft, with a Mohs hardness of 6.5 to 7, and it is known for its fine-grained texture, which allows for detailed carvings. It is commonly used in cameos, intaglios, and rings, especially when set in yellow or white gold.
Spinel: A Diverse and Durable Gem
Spinel is a garnet group mineral, with a chemical composition of MgAl₂O₄. It forms in igneous and metamorphic rocks, and it is known for its wide range of colors, which are caused by different trace elements.
The most sought-after spinel colors include:
- Red and pink: Due to the presence of chromium or magnesium.
- Blue: Due to cobalt.
- Black: Due to iron.
Major sources of spinel include:
- Afghanistan, Myanmar, and Sri Lanka: Known for producing high-quality red and pink spinels.
- Brazil, Tanzania, and Vietnam: Additional sources for a variety of spinel colors.
Spinel has a Mohs hardness of 8, making it a durable and scratch-resistant gemstone. It is often used in rings, earrings, and pendants, and it is particularly popular in vintage and antique jewelry.
Gemological Properties
Understanding the scientific properties of a gemstone is essential for both identification and appreciation. Below is a detailed breakdown of the gemological properties of the three August birthstones.
Peridot
| Property | Description |
|---|---|
| Chemical Formula | Mg₂SiO₄ |
| Crystal System | Orthorhombic |
| Mohs Hardness | 6.5 – 7 |
| Specific Gravity | 3.3 – 4.5 |
| Refractive Index | 1.650 – 1.690 |
| Color | Green (yellow-green to olive green) |
| Transparency | Transparent to translucent |
| Luster | Vitreous |
| Inclusions | Common, including tiny crystals and “horsetail” inclusions |
| Cleavage | Perfect in one direction |
| Origin of Name | From the Arabic word "faridat," meaning gem |
Peridot is known for its vibrant green color, which is caused by the presence of iron. The most valuable peridots are those with a deep, vivid green color and minimal inclusions.
Sardonyx
| Property | Description |
|---|---|
| Chemical Formula | SiO₂ (with iron oxides) |
| Crystal System | Trigonal |
| Mohs Hardness | 6.5 – 7 |
| Specific Gravity | 2.58 – 2.64 |
| Refractive Index | 1.48 – 1.53 |
| Color | Banded red, brown, and white |
| Transparency | Translucent to opaque |
| Luster | Waxy to vitreous |
| Inclusions | Typically free of inclusions |
| Cleavage | No cleavage |
| Origin of Name | From the Latin "sardonyx," combining "sardis" (Sardinia) and "onyx" |
Sardonyx is a banded variety of chalcedony, and its distinct red and white bands make it ideal for cameo and intaglio carvings. It is known for its fine-grained texture and smooth surface, which allow for intricate detailing.
Spinel
| Property | Description |
|---|---|
| Chemical Formula | MgAl₂O₄ |
| Crystal System | Cubic |
| Mohs Hardness | 8 |
| Specific Gravity | 3.98 – 4.10 |
| Refractive Index | 1.718 – 1.736 |
| Color | Red, pink, orange, blue, black |
| Transparency | Transparent to translucent |
| Luster | Vitreous |
| Inclusions | Rare, but can include small inclusions |
| Cleavage | No cleavage |
| Origin of Name | From the Latin word "spina," meaning spine or thorn |
Spinel is known for its brilliance and fire, which are comparable to those of ruby and sapphire. It is highly durable and is suitable for daily wear. The red and pink varieties are especially popular for August birthstone jewelry.
Symbolism and Metaphysical Beliefs
Each of the August birthstones carries its own symbolism and metaphysical significance, rooted in ancient traditions and modern beliefs.
Peridot: The Stone of Abundance and Protection
Peridot is often associated with positive energy, abundance, and protection. In ancient Egypt, it was used to ward off nightmares and bring happiness. It was also believed to promote courage and strength, making it a popular stone for warriors and leaders.
Modern metaphysical beliefs suggest that peridot is a Heart Chakra stone, helping to open the heart to love and healing. It is also believed to remove negative emotions and promote optimism, making it a popular stone for those seeking inner peace and joy.
Sardonyx: The Stone of Stability and Courage
Sardonyx is a protective and stabilizing stone, often used to promote courage, strength, and clarity. In ancient Rome, it was believed to ward off envy and strengthen the will, making it a popular stone for leaders and warriors.
Modern metaphysical beliefs suggest that sardonyx supports emotional balance and mental focus. It is also believed to promote strong, lasting relationships and is often used in engagement rings and wedding jewelry.
Spinel: The Stone of Vitality and Inspiration
Spinel is a high-energy stone associated with renewal, inspiration, and vitality. In medieval Europe, it was used to boost energy and restore strength, and it was especially popular among royal families and nobility.
Modern metaphysical beliefs suggest that spinel is a stone of passion and creativity, helping to ignite inspiration and restore hope. It is also believed to support emotional healing and encourage bold decision-making.
Care and Cleaning
Each of the August birthstones has its own care requirements, based on its hardness, cleavage, and sensitivity to chemicals.
Peridot
- Hardness: 6.5 – 7 (moderately hard)
- Cleavage: Perfect in one direction
- Cleaning: Use mild soap and warm water. Avoid ammonia, bleach, or harsh chemicals.
- Storage: Store peridot separately from harder gemstones to avoid scratches.
Sardonyx
- Hardness: 6.5 – 7 (moderately hard)
- Cleavage: No cleavage
- Cleaning: Use mild soap and warm water. Avoid exposure to high heat or strong chemicals.
- Storage: Store sardonyx in a soft cloth or padded box to protect carved surfaces.
Spinel
- Hardness: 8 (very hard)
- Cleavage: No cleavage
- Cleaning: Use mild soap and warm water. Spinel is very durable and can be ultrasonically cleaned.
- Storage: Store spinel in a dry, cool place to prevent tarnishing of the metal setting.
Conclusion
The August birthstones—peridot, sardonyx, and spinel—offer a rich tapestry of history, beauty, and meaning. From the ancient Egyptians’ love for peridot to the Roman use of sardonyx in cameos, and from the royal history of spinel to its recent recognition as an official birthstone, these gems have played significant roles in different cultures and eras.
Whether you're drawn to the vibrant green of peridot, the bold bands of sardonyx, or the sparkling versatility of spinel, each of these gemstones offers a unique way to celebrate your birth month and connect with the energy and symbolism of summer.
As you explore the world of August birthstones, consider which one speaks to you most. Whether for personal style, spiritual connection, or historical significance, these stones are a beautiful and meaningful way to honor your birth month.