August, the third month of the summer season, is uniquely distinguished by not one, but three birthstones: peridot, spinel, and sardonyx. Each of these gems has its own compelling history, distinct gemological properties, and rich cultural associations. While peridot is often highlighted as the most vibrant and recognizable of the three, spinel and sardonyx contribute equally to the diverse tapestry of August’s birthstone legacy. This article delves into the scientific, historical, and cultural aspects of these three stones, offering a comprehensive understanding of why they are celebrated together as August’s birthstones.
Introduction
August is the only month in the calendar year to boast three official birthstones: peridot, spinel, and sardonyx. This triad reflects both the historical evolution of birthstone traditions and the expanding appreciation for gem diversity among collectors and jewelers. Peridot, with its striking green hue and cosmic origins, is often the most recognized of the group. Spinel, once mistaken for ruby and now gaining newfound appreciation, brings a fiery brilliance to the collection. Sardonyx, an ancient stone with a storied past, completes the trio with its distinctive banding of red and white.
Each of these gemstones has its own unique journey, from the depths of Earth’s mantle and meteorites to the royal courts of Europe and the sacred altars of ancient temples. The inclusion of these stones in the birthstone tradition not only reflects their beauty but also their historical significance and enduring appeal. This article explores the geological formation, historical use, symbolic meanings, and practical care of each gemstone, drawing from authoritative sources in the field of gemology.
History and Lore
The Origins of the August Birthstone Tradition
The tradition of birthstones dates back centuries, with roots in both ancient and medieval cultures. The concept is believed to have originated from the Breastplate of Aaron, described in the Hebrew Bible, which contained twelve gemstones representing the twelve tribes of Israel. Over time, these stones were associated with the months of the year and the zodiac signs.
In the case of August, sardonyx has the longest-standing tradition as its birthstone. Sardonyx is a type of chalcedony, a form of quartz, characterized by its banded layers of sard (a reddish-brown chalcedony) and onyx (a black or white chalcedony). This stone has been used for thousands of years in amulets, signet rings, and decorative objects. Ancient Egyptians, Greeks, and Romans valued sardonyx for its protective properties and believed it could ward off evil and bring good fortune.
The addition of peridot to the August birthstone lineup came much later. According to sources from the Jewelers of America, peridot was officially recognized as an August birthstone in 1912. This decision reflected the growing appreciation for gemstone diversity and the ability of jewelers to identify and market specific stones with greater accuracy.
In 2016, the list was further expanded with the inclusion of spinel. Spinel, a gemstone that had long been confused with ruby due to its similar appearance and color, was finally given its due recognition. The addition of spinel not only broadened the options available to August babies but also helped raise awareness about this beautiful and versatile gemstone.
Peridot: The "Gem of the Sun"
Peridot has one of the most fascinating histories among the August birthstones. Known as the "gem of the sun," it has been cherished for its vibrant green color and its association with positive energy. Ancient Egyptians, who were among the first to mine peridot, believed it protected against nightmares and brought health and confidence to the wearer. They sourced most of their peridot from the volcanic island of Zabargad in the Red Sea, a place so harsh and dangerous it was known as the "Island of Death."
Peridot was also highly valued in medieval Europe. Priests wore it in their rings and used it to decorate chalices and church altars. During the Victorian era, peridot jewelry became fashionable, particularly for mourning jewelry due to its subdued yet elegant green tones.
A particularly intriguing historical detail is the Shrine of the Three Holy Kings in Cologne Cathedral, Germany. This shrine is adorned with 200 carats of gems that were originally believed to be emeralds. However, modern gemological analysis has confirmed that these gems are actually peridot, highlighting the gem’s historical significance and the potential for misidentification in the past.
Sardonyx: The Ancient Guardian
Sardonyx, the original August birthstone, has a history that stretches back over 4,000 years. It was used in ancient Egypt for amulets and signet rings and was believed to provide protection and strength. The stone was also popular in the Roman Empire, where it was used for engraved seals and decorative objects.
The banding pattern of sardonyx, with its alternating layers of red and white, made it ideal for engraving and was often used in intaglios (carved gems used as seals). These were used to sign documents and as personal identifiers for Roman officials and aristocrats.
Sardonyx is also associated with chastity and purity, making it a favored stone for use in wedding rings and religious ceremonies. Its durability and affordability made it accessible to a wide range of people, contributing to its enduring popularity.
Spinel: The Rediscovered Gem
Spinel has a more recent and intriguing history. For centuries, it was mistaken for ruby, especially in red varieties. One of the most famous examples is the "Balas Ruby" from the Crown Jewels of the United Kingdom, which was later identified as a large red spinel. This misidentification was due to the similarity in color and refractive properties between certain spinel and ruby specimens.
The 2016 recognition of spinel as an August birthstone marked a turning point for the gemstone. It helped correct the historical oversight and introduced spinel to a new generation of gem lovers. Spinel is now appreciated for its brilliance, clarity, and wide range of colors, from deep reds and purples to vibrant pinks and blues.
Geological Formation and Sources
Peridot: A Gem from Earth and Space
Peridot is a naturally occurring variety of the mineral olivine, with a chemical formula of Mg₂SiO₄ to Fe₂SiO₄, depending on its iron content. It forms under extreme heat and pressure in the Earth’s mantle and is brought to the surface through volcanic activity. This is why peridot is often found in basaltic lava flows and meteorites — making it one of the few gemstones that can be said to originate from both the Earth and outer space.
Peridot is also known as the "Hawaiian stone," as it has been found in volcanic lava in Hawaii. The green sands of Peridot Beach in Hawaii are a result of peridot-rich volcanic rock being eroded over time. These sands shimmer with a luminous green and are a popular attraction for tourists.
The finest peridot historically came from the Red Sea island of Zabargad, also known as Topazios. This island was the primary source of peridot for the ancient Egyptians and remained an important source until the early 20th century. Today, peridot is mined in countries such as China, Myanmar, Pakistan, Tanzania, Vietnam, and the United States.
Spinel: A Versatile and Durable Gemstone
Spinel is a garnet mineral with a chemical composition of MgAl₂O₄, though it can vary in composition depending on the presence of other elements like iron, chromium, or magnesium. It forms in metamorphic and igneous rocks, particularly in areas where there has been magmatic activity.
Spinel is known for its high hardness on the Mohs scale (8), making it durable and suitable for everyday wear. It is also highly refractive, which gives it a sparkling brilliance that is often compared to that of ruby or sapphire.
The most famous historical sources of spinel include Afghanistan, Burma, and Sri Lanka. These regions were known for producing large, high-quality spinel stones that were often mistaken for rubies. The "Balas Ruby" in the British Crown Jewels is a prime example of this historical misidentification.
Today, spinel is mined in Brazil, Madagascar, Myanmar, and Tanzania, among other countries. Its availability in a wide range of colors makes it a versatile and appealing gemstone for jewelry designers and collectors alike.
Sardonyx: A Chalcedony with a Rich Past
Sardonyx is a banded variety of chalcedony, a form of microcrystalline quartz. It is composed of sard (a reddish-brown chalcedony) and onyx (a black or white chalcedony) in alternating layers. This banding pattern makes it ideal for engraving and carving.
Sardonyx forms in sedimentary and volcanic rocks, particularly in areas where quartz-rich solutions have infiltrated cavities and cooled over time. This process results in the distinct banding that is characteristic of the stone.
Historically, sardonyx was mined in Egypt, India, and the Near East. It was highly prized for its durability and was used in signet rings, amulets, and ceremonial objects. Today, sardonyx is still mined in India, Brazil, and the United States, and it remains a popular choice for engraved jewelry and decorative objects.
Gemological Properties
Peridot
| Property | Description |
|---|---|
| Color | Yellow-green to greenish-yellow |
| Chemical Composition | (Mg, Fe)₂SiO₄ |
| Hardness (Mohs Scale) | 6.5 to 7 |
| Refractive Index | 1.65 to 1.70 |
| Specific Gravity | 3.27 to 4.35 |
| Transparency | Transparent to translucent |
| Luster | Vitreous |
| Cleavage | Perfect in two directions |
| Origin | Earth's mantle, meteorites |
| Cutting Style | Often cut as a brilliant or emerald cut |
Peridot’s color is due to the presence of iron in its crystal structure. The more iron present, the deeper the green color. This gemstone is not typically treated or enhanced, as it is already naturally colorful and beautiful.
Spinel
| Property | Description |
|---|---|
| Color | Red, pink, purple, blue, orange, black |
| Chemical Composition | MgAl₂O₄ (with variations due to impurities) |
| Hardness (Mohs Scale) | 8 |
| Refractive Index | 1.718 to 1.757 |
| Specific Gravity | 3.98 to 4.10 |
| Transparency | Transparent to translucent |
| Luster | Vitreous |
| Cleavage | None |
| Origin | Metamorphic and igneous rocks |
| Cutting Style | Round brilliant, emerald, and other faceting styles |
Spinel is highly versatile in terms of color and is known for its high refractive index and excellent brilliance. Unlike peridot, it is very durable due to its high hardness and lack of cleavage, making it suitable for a wide range of jewelry applications.
Sardonyx
| Property | Description |
|---|---|
| Color | Banded red and white (sard and onyx) |
| Chemical Composition | Silica (SiO₂) |
| Hardness (Mohs Scale) | 6.5 to 7 |
| Refractive Index | 1.48 to 1.53 |
| Specific Gravity | 2.58 to 2.61 |
| Transparency | Translucent |
| Luster | Waxy to vitreous |
| Cleavage | None |
| Origin | Sedimentary and volcanic rocks |
| Cutting Style | Often carved or engraved |
Sardonyx is not typically faceted but is instead carved or engraved to highlight its banding. It is very durable and resistant to damage, making it a popular choice for signet rings and engraved pendants.
Symbolism and Metaphysical Beliefs
Peridot: Light and Energy
Peridot has long been associated with positive energy, light, and protection. The ancient Egyptians believed it could ward off nightmares and bring health and confidence to the wearer. It was also believed to have healing properties, particularly for the digestive system and liver.
In Hawaiian tradition, peridot is associated with volcanic activity, and it was believed to be the tears of the goddess Pele, the goddess of fire and volcanoes. These tears were said to be brought to the surface through volcanic eruptions.
Peridot is also believed to promote emotional healing and reduce stress. It is often used in spiritual practices to help with manifestation, clarity, and inner peace.
Spinel: Passion and Clarity
Spinel is often associated with passion, vitality, and emotional clarity. In historical times, it was believed to protect the wearer from harm and bring good fortune. Red spinel, in particular, was associated with love and power, much like ruby.
Spinel is also believed to enhance communication and self-expression, making it a popular choice for those who are seeking to improve their social and professional relationships.
Sardonyx: Strength and Protection
Sardonyx has long been associated with strength, protection, and discipline. Ancient cultures believed it could ward off evil spirits and protect the wearer from negative influences. It was also believed to enhance willpower and self-control, making it a popular choice for warriors and leaders.
Sardonyx is also associated with chastity and purity, making it a popular choice for use in wedding rings and religious ceremonies.
Care and Cleaning
Peridot
Peridot has a hardness of 6.5 to 7 on the Mohs scale, making it relatively durable, but it can still be damaged by hard knocks or abrasion. It also has a perfect cleavage in two directions, so it should be handled carefully.
- Cleaning: Peridot can be cleaned with a soft cloth and mild soap and water. Avoid using ultrasonic or steam cleaners, as they can potentially damage the stone or its setting.
- Storage: Store peridot jewelry in a soft cloth or padded box to prevent scratching or chipping.
Spinel
Spinel is very durable, with a hardness of 8 on the Mohs scale and no cleavage, making it ideal for everyday wear.
- Cleaning: Spinel can be cleaned with ultrasonic or steam cleaners, as well as with mild soap and water.
- Storage: Store spinel jewelry in a soft cloth or padded jewelry box to prevent scratching.
Sardonyx
Sardonyx is quite durable, with a hardness of 6.5 to 7 on the Mohs scale and no cleavage, making it resistant to damage.
- Cleaning: Sardonyx can be cleaned with mild soap and water or a soft cloth. Avoid using harsh chemicals or abrasive cleaners, as they can damage the stone’s surface.
- Storage: Store sardonyx jewelry in a padded box to prevent scratching, especially if it is engraved or carved.
Conclusion
The August birthstones — peridot, spinel, and sardonyx — each bring their own unique charm and significance to the month. Peridot, with its vibrant green color and cosmic origins, is a symbol of light and positivity. Spinel, once mistaken for ruby, is now gaining well-deserved recognition for its brilliance and versatility. Sardonyx, the original August birthstone, has a long and storied history that spans thousands of years.
Together, these three gemstones reflect the diversity, beauty, and enduring appeal of August’s birthstone tradition. Whether you are drawn to the sparkling reds of spinel, the luminous green of peridot, or the banded elegance of sardonyx, there is a perfect gemstone to celebrate the spirit of August.