August is a unique month in the realm of birthstones, offering not one, but three distinct official gemstones: peridot, spinel, and sardonyx. This trio provides individuals born in this summer month with a diverse palette of colors, histories, and meanings to choose from. While peridot is often the most recognized for its vibrant green hue, spinel offers a spectrum of colors with a history of being mistaken for more precious gems, and sardonyx, the traditional stone, boasts an ancient lineage tied to carving and symbolism. Each stone possesses unique gemological properties, origins, and cultural narratives that reflect the warmth and strength of the season. This article explores the geological formation, historical significance, gemological characteristics, and metaphysical beliefs associated with each of August’s birthstones, providing a comprehensive guide for enthusiasts, collectors, and those seeking a personal connection to these remarkable minerals.
The Triad of August: An Introduction to the Month’s Birthstones
The concept of birthstones has evolved over centuries, with traditions varying across cultures and time. In the modern context, particularly in the United States, the list of birthstones was standardized in 1912 by the American Gem Trade Association (AGTA) and Jewelers of America (JA). Peridot was established as the official August birthstone at that time. However, the tradition was later expanded to offer greater choice in color, affordability, and availability. Sardonyx, the original and traditional August birthstone, has a history dating back over 4,000 years. More recently, in 2016, spinel was added to the official list, completing the trio. This addition acknowledges spinel’s historical significance and its growing popularity as an alternative to ruby and other precious stones.
The three stones are geologically distinct. Peridot is a variety of the mineral olivine, formed under extreme conditions both within the Earth and from extraterrestrial sources. Spinel is a separate mineral species, historically confused with ruby but now appreciated for its own merits. Sardonyx is a banded variety of chalcedony, a microcrystalline form of quartz. Their differing compositions result in a range of colors, hardness, and care requirements. Understanding these differences is key to appreciating the full spectrum of August’s birthstones and making an informed choice for jewelry or personal collection.
Peridot: The Green Gem of the Sun and Mantle
History and Lore
Peridot, the yellowish-green to greenish-yellow gem variety of the mineral olivine, has a rich and often misunderstood history. The word “peridot” is derived from the Arabic faridat, meaning “gem.” Throughout history, its vibrant green color led to frequent confusion with other precious stones. The Red Sea island of Topazios, a source that contributed to the name “topaz,” was actually a producer of peridot. Perhaps the most famous example of this historical misidentification is found in Germany’s Cologne Cathedral. The Shrine of the Three Holy Kings is adorned with 200 carats of gems long believed to be emeralds; modern analysis confirms they are, in fact, peridot. Some historians even speculate that Cleopatra’s legendary emerald collection may have contained peridot.
Ancient cultures prized peridot for its beauty and believed it held protective powers. It was thought to ward off nightmares and bring the wearer happiness and strength. The Egyptians mined peridot on the island of Zabargad (St. John’s Island) in the Red Sea as early as the 4th century B.C. These stones were highly valued and used in jewelry and ceremonial objects. The Romans also held peridot in high esteem, calling it the “evening emerald” because its green color does not darken at night but remains visible under candlelight. This luminous quality contributed to its association with the sun and positive energy.
Geological Formation and Sources
Peridot’s formation is remarkable for its occurrence in two very different environments: deep within the Earth’s mantle and in meteorites from outer space. As the gem variety of olivine, it is brought to the Earth’s surface through volcanic activity. Massive eruptions sent rivers of lava carrying olivine from the mantle to the surface. In the United States, Arizona is the primary source of peridot. The most significant deposits are found on the San Carlos Apache Indian Reservation, where some Apache families have mined the stones for decades. The finest-quality peridot from this locality is noted for its deep color and superb transparency.
In addition to terrestrial sources, peridot has arrived on Earth via pallasite meteorites. These meteorites are composed of nickel-iron and olivine. While thousands of meteorites have struck Earth and many contain olivine, only a few yield gem-quality peridot suitable for use in jewelry. These extraterrestrial peridots are exceptionally rare and prized by collectors for their unique origin story.
Gemological Properties
Peridot is a relatively hard gemstone, rating 6.5 to 7 on the Mohs scale of hardness. This places it in a moderate range, making it durable enough for jewelry but softer than many popular gems like sapphire or diamond. Consequently, peridot is not recommended for daily wear in rings, especially for individuals with active lifestyles, as it can be susceptible to scratches and abrasions.
The gem’s color is its most defining characteristic, ranging from bright lime green to a deeper olive green. The primary cause of this color is the presence of iron within the crystal structure. Peridot is typically transparent and can be found in large sizes, making it an excellent choice for statement jewelry pieces like pendants and earrings. However, like many gemstones, peridot can contain inclusions, which are natural internal features. High-quality peridot is valued for its clarity and vibrant, saturated color without being overly dark.
Metaphysical Beliefs
In modern crystal healing and metaphysical practices, peridot is associated with positive energy and emotional well-being. It is often called the “stone of the sun” and is believed to bring light and joy to the wearer. Peridot is linked to the heart chakra and is thought to support healing, release negative patterns, and open the heart to love and abundance. It is also considered a stone for boosting confidence, mood, and prosperity. These beliefs, while not scientifically proven, contribute to the stone’s enduring appeal as a meaningful gift.
Care and Cleaning
Due to its moderate hardness and sensitivity, peridot requires careful handling and cleaning. It should be protected from hard blows and abrasive surfaces. The gem is vulnerable to thermal shock and can be damaged by sudden temperature changes, so it should never be cleaned with steam or ultrasonic cleaners. Acids and even long-term exposure to acidic perspiration can also harm peridot. The safest cleaning method is to use a soft-bristle brush with a mild dish soap in warm water, followed by thorough rinsing and drying with a soft cloth. When storing peridot jewelry, it should be kept separately or wrapped in a soft cloth to prevent scratching by harder gems.
Spinel: The Underappreciated Royal Gem
History and Lore
Spinel’s history is intertwined with that of ruby, as red spinel was mistaken for the more precious gem for centuries. The most famous example is the “Black Prince’s Ruby” in the British Imperial State Crown, which is actually a massive red spinel. Similarly, the Timur Ruby, another historic stone in the British Crown Jewels, is also a spinel. These stones were often sourced from the famed mines of Badakhshan in Central Asia (modern-day Afghanistan and Tajikistan). For much of history, spinel was underappreciated, often referred to as “balas ruby” or simply considered a variety of ruby.
It was not until the 19th century that spinel was recognized as a distinct mineral species, separate from ruby and corundum. This scientific distinction paved the way for spinel to be appreciated for its own unique qualities. Today, spinel is valued as a standalone gemstone, prized for its brilliance, durability, and wide range of colors. Its addition as an official August birthstone in 2016 reflects its growing recognition in the gem trade and its appeal as a vibrant, more affordable alternative to ruby.
Geological Formation and Sources
Spinel is a magnesium aluminum oxide (MgAl₂O₄) and forms under high-temperature and high-pressure metamorphic conditions, often in association with minerals like corundum and ruby. It can also be found in alluvial deposits, having been eroded from primary sources over time.
Historically, the most important sources of spinel were in Asia. The mines of Badakhshan, particularly in the Kuh-i-Lal region, produced some of the world’s finest red spinels. These stones traveled along the Silk Road and were coveted by royalty across continents. Today, spinel is mined in several locations worldwide. Notable sources include: * Myanmar (Burma): Known for producing high-quality red and pink spinels. * Vietnam: A significant source for vibrant pink and blue spinels. * Tajikistan: Continues to produce spinel, including the famed “red” variety. * Sri Lanka: Produces a variety of spinel colors, including blue and pink. * Other sources: Spinel is also found in Cambodia, Brazil, Australia, and the United States (New York and North Carolina).
Gemological Properties
Spinel is a durable gemstone with a hardness of 8 on the Mohs scale, making it excellent for all types of jewelry, including rings and bracelets, as it resists scratching and abrasion well. Its refractive index is moderate, and it typically lacks the strong pleochroism seen in many other gems, meaning its color appears consistent from different viewing angles.
One of spinel’s most appealing features is its extensive color range. While the most famous and valuable spinels are red (often mistaken for ruby), the gem also occurs naturally in a wide spectrum of hues, including vibrant pink, orange, purple, blue, and even black. The red color is caused by chromium, while iron and other trace elements contribute to other colors. Spinel is generally transparent and can display excellent brilliance and clarity. Unlike many colored gems, large, clean spinels of desirable colors are relatively available, making them an attractive option for significant jewelry pieces.
Metaphysical Beliefs
In the realm of crystal healing, spinel is associated with revitalization and energy. Different colors are believed to hold specific properties. Red spinel is linked to vitality and passion, while blue spinel is thought to promote calm and communication. Pink spinel is associated with love and emotional healing. Overall, spinel is considered a stone of renewal, inspiration, and grounding. It is believed to help restore energy, inspire hope, and provide encouragement during difficult times. Its vibrant colors and energetic associations make it a popular choice for those seeking a gem with both beauty and symbolic meaning.
Care and Cleaning
Spinel’s high hardness of 8 on the Mohs scale makes it a relatively low-maintenance gemstone. It is resistant to scratches from most everyday materials and can withstand regular wear. However, like all gemstones, it can be chipped or broken by a hard impact. Spinel is generally stable when exposed to light and heat, making it safe for most jewelry-making processes. It can be cleaned using warm, soapy water and a soft brush. Ultrasonic cleaners are typically safe for untreated spinel, but caution is advised for stones that may have been treated or set in delicate jewelry. Steam cleaning should be avoided for stones with inclusions or fractures, as the heat and pressure can cause damage.
Sardonyx: The Ancient Carving Stone
History and Lore
Sardonyx, a banded variety of chalcedony, is the traditional and original August birthstone, with a history stretching back over 4,000 years. It is composed of alternating layers of sard (a brownish-red to orange variety of chalcedony) and onyx (typically black or white chalcedony). This banding made sardonyx an ideal material for carving cameos and intaglios, where the contrasting layers could be used to create detailed images. In ancient Rome, sardonyx was particularly popular for seals and signet rings. Its surface was ideal for this purpose because hot wax would not stick to it, ensuring a clean impression.
Sardonyx is mentioned in the Old Testament as one of the stones in the High Priest’s breastplate, symbolizing the strength of spiritual life. Roman soldiers wore rings carved with the image of Mars, the god of war, believing sardonyx would grant them protection in battle. This association with courage and protection has persisted through history. Today, sardonyx is linked to happiness, clear communication, and stability in relationships and marriage.
Geological Formation and Sources
Sardonyx is a form of microcrystalline quartz (silicon dioxide). It forms in volcanic or metamorphic rocks, where silica-rich solutions deposit layers of chalcedony in cavities or fractures. The banding occurs as the composition of the silica solution changes over time, depositing different colors (sard and onyx) in successive layers. This natural process creates the distinctive striped appearance.
Sardonyx is found in many locations around the world. Notable sources include: * India: Particularly known for producing sardonyx with excellent contrast between the dark and light layers, ideal for carving. * Brazil: A significant source of various chalcedony varieties, including sardonyx. * Germany and Czech Republic: Historical sources of quality sardonyx. * Madagascar and Uruguay: Modern sources of chalcedony, including banded varieties. * United States: Sardonyx is found in several states, including Oregon and California.
Gemological Properties
Sardonyx has a hardness of 6.5 to 7 on the Mohs scale, similar to peridot. This makes it suitable for jewelry but requires care to avoid scratches and impacts, especially in rings. It is a member of the quartz family, with a hardness that is moderate but durable enough for most jewelry applications.
The defining feature of sardonyx is its banding. The color bands range from brownish-red to brown and dark orange (sard) interlayered with typically white or black (onyx). The quality of sardonyx is often judged by the sharpness and contrast of these bands. While naturally occurring, it is important to note that sardonyx, like other forms of chalcedony, is commonly dyed to enhance or create banding patterns. This treatment is generally stable but can be affected by heat. High heat, such as that used in jewelry manufacturing or repair, may alter the color of dyed sardonyx.
Metaphysical Beliefs
Sardonyx is deeply connected to ancient symbolism and is considered a stone of strength, courage, and protection. Its earthy, grounded energy is believed to provide stability and support, particularly in relationships and partnerships. In modern metaphysical practices, sardonyx is associated with clear communication, happiness, and steadfastness. It is often recommended for those seeking to build resilience, overcome fear, and foster a sense of security. Its historical use as a protective talisman in battle lends credibility to its modern reputation as a grounding stone that brings stability and courage to the wearer.
Care and Cleaning
Caring for sardonyx involves considerations similar to those for peridot due to its comparable hardness. It should be protected from hard impacts and abrasive surfaces. As a form of chalcedony, it is generally stable but can be sensitive to heat, especially if dyed. Therefore, ultrasonic and steam cleaners should be used with caution. The safest cleaning method is warm, soapy water and a soft brush. For dyed sardonyx, it is best to avoid any cleaning methods that involve heat or harsh chemicals to preserve the color. When storing sardonyx jewelry, keep it separate from harder gems to prevent scratching.
Conclusion
August’s trio of birthstones—peridot, spinel, and sardonyx—offers a remarkable diversity that reflects the richness of the summer month. Peridot, with its vibrant green hue born from the Earth’s mantle and meteorites, carries a history of mistaken identity and associations with light and joy. Spinel, the durable and colorful gem once confused with ruby, now stands in its own right as a symbol of renewal and vitality, available in a spectrum from red to blue. Sardonyx, the ancient banded stone, provides a tangible link to millennia of human history, from Roman seals to biblical breastplates, embodying strength and communication.
Each stone presents unique gemological properties, from the moderate hardness of peridot and sardonyx to the superior durability of spinel, influencing their care and suitability for different jewelry types. Their metaphysical beliefs, while rooted in cultural traditions rather than scientific fact, add a layer of personal significance for many wearers. Ultimately, the choice among these three gems allows August-born individuals to select a stone that resonates with their personal style, budget, and the symbolic meaning they wish to carry. Whether drawn to the sunlit green of peridot, the royal history of spinel, or the ancient artistry of sardonyx, each gemstone is a testament to the enduring beauty and fascinating science of the mineral world.