August is a unique month in the gemological calendar, distinguished by not one, but three official birthstones: Peridot, Spinel, and Sardonyx. This triad offers a remarkable spectrum of color, history, and origin, bridging the vibrant energy of summer with the approach of autumn. While Peridot is often celebrated for its distinct lime-green hue, Spinel provides a history of mistaken identity with ruby, and Sardonyx stands as the ancient original with a legacy spanning over four millennia. The evolution of the August birthstone list reflects a broader trend in gemology: a shift from rigid tradition to a more inclusive approach that values consumer choice, availability, and the diverse beauty of the mineral kingdom. This article explores the geological formation, gemological properties, historical lore, and cultural significance of these three captivating gems, providing a comprehensive guide for enthusiasts, collectors, and those born in the eighth month of the year.
The Historical Evolution of August's Birthstones
The concept of associating specific gemstones with birth months is an ancient practice, with roots in the biblical breastplate of Aaron, which was set with twelve gems representing the twelve tribes of Israel. Over centuries, this tradition evolved, with various cultures assigning stones based on zodiac signs or calendar months. However, the modern, standardized birthstone list is a relatively recent development.
The pivotal moment for birthstone standardization occurred in 1912 when the American National Retail Jewelers Association, now known as Jewelers of America, convened to create an official chart. This list was designed to provide a consistent guide for the jewelry trade and consumers. In this initial compilation, Peridot was designated as the sole birthstone for August. This choice likely reflected the gem's growing availability and popularity in the early 20th century.
For over a century, Peridot held this position alone. Yet, the list continued to evolve. The original August gem, as noted in several sources, was actually Sardonyx. This banded variety of onyx had been associated with the month for over 4,000 years, particularly in Roman culture, before being superseded. The journey did not end there. In 2016, the American Gem Trade Association (AGTA) and Jewelers of America updated the list again, officially adding Spinel. This decision was driven by a desire to offer consumers more variety in terms of color and price point, and to recognize a gem that had been historically underappreciated and often mistaken for other stones like ruby.
While Peridot and Spinel are the two stones officially recognized by the major trade organizations in the United States, Sardonyx retains a strong "traditional" status. Furthermore, some lists also include Onyx (a distinct variety of banded chalcedony) as a third option, acknowledging its long-standing association with the month. This layered history—encompassing ancient tradition, early 20th-century standardization, and modern updates—makes August's selection of birthstones one of the most diverse and historically rich of any month.
Peridot: The Green Gem of the Sun
Peridot stands as the most recognized and traditional of the August birthstones. Its signature color, a vibrant lime-green to olive hue, sets it apart from almost all other gems. This distinct color is not a result of trace impurities, as is common in gemology, but is an intrinsic part of its chemical composition.
Geological Formation and Origin
Peridot is the yellowish-green to greenish-yellow gem variety of the mineral olivine. The name "olivine" is derived from the Latin word oliva, meaning olive, a direct reference to its common color. The formation of Peridot is one of the more extraordinary stories in the gem world. While many gems crystallize in the Earth's crust, Peridot is formed deep within the Earth's mantle under extreme conditions of intense heat and pressure. It is then brought to the surface by volcanic activity.
Specific sources highlight its unique origins, noting that this August birthstone can be found in hardened lava that carries it from deep within the mantle. This is why Peridot is often found in volcanic regions. Adding to its mystique, some Peridot is extraterrestrial. The sources mention that this gem can also be found in meteorites that traveled from outer space, making it one of the few gems with confirmed cosmic origins. Historically, a significant source of Peridot was the island of Zabargad (formerly Topazios) in the Red Sea. This island was a source of confusion for ancients, who mistook the green Peridot for Topaz, which is how the island got its name.
Gemological Properties
Peridot is a relatively hard and durable gemstone, making it suitable for all types of jewelry, including rings and daily-wear pieces. Its key properties are as follows:
| Property | Description |
|---|---|
| Mineral | Olivine |
| Chemical Formula | (Mg, Fe)₂SiO₄ |
| Hardness (Mohs Scale) | 6.5 - 7 |
| Crystal System | Orthorhombic |
| Refractive Index | 1.65 - 1.69 |
| Luster | Vitreous (glass-like) |
| Typical Colors | Yellowish-green to greenish yellow |
Its hardness of 6.5 to 7 on the Mohs scale makes it durable enough for jewelry, though care should be taken to avoid hard knocks or abrasions. The vitreous luster gives it a brilliant shine when properly cut and polished.
History and Lore
Throughout history, Peridot has been a gem of fascination and frequent misidentification. The sources provide several compelling examples. The Shrine of the Three Holy Kings in Germany’s Cologne Cathedral is adorned with 200 carats of gems that were believed for centuries to be emeralds but are, in fact, Peridot. This confusion was common; ancient Egyptians mined Peridot on Zabargad and called it the "gem of the sun," believing it held protective powers against the terrors of the night. Some historians even speculate that Cleopatra's famed collection of emeralds may have actually been Peridot.
The name "Peridot" itself is thought to derive from the Arabic word faridat, meaning gem. In medieval times, it was used to decorate churches and was worn by clergy. Its lore is tied to light and positivity, with beliefs that it could dispel darkness and fear, bringing the wearer happiness and strength.
Symbolism and Metaphysical Beliefs
Metaphysically, Peridot is associated with light, positivity, and abundance. Its bright green color is linked to growth, renewal, and the vitality of nature. Beliefs hold that it can open the heart to joy and new relationships, while also providing protection against negative energies. Its connection to the sun in ancient Egyptian lore reinforces its symbolism as a stone of warmth, light, and life-giving energy.
Care and Cleaning
Due to its hardness of 6.5 to 7, Peridot is reasonably durable but does have some susceptibility to chipping if struck with force. It has no cleavage, which is a benefit, but it is still wise to protect it from sharp blows. For cleaning, warm, soapy water and a soft brush are recommended. Ultrasonic cleaners are generally safe, but steam cleaning is not advised due to the potential for thermal shock. Sudden temperature changes should be avoided.
Spinel: The Underappreciated Ruby Impostor
For centuries, Spinel was the unsung hero of the gem world, often living in the shadow of more famous stones. Its addition to the official August birthstone list in 2016 was a long-overdue recognition of its own intrinsic beauty and value.
Geological Formation and Origin
Spinel is a magnesium aluminum oxide with a cubic crystal system. It forms in metamorphic rocks, often in association with ruby and sapphire in placer deposits. While it can be found in many locations, some of the most historically significant sources include Burma (now Myanmar), Sri Lanka, and Tajikistan. The famous "Black Prince's Ruby" in the British Imperial State Crown is, in fact, a large red Spinel. Similarly, the "Timur Ruby" is another massive red Spinel. For centuries, these and other large red spinels were mistaken for rubies, leading to the gem being underappreciated.
Gemological Properties
Spinel boasts an impressive set of physical properties, some of which rival or exceed those of ruby and sapphire. It is highly durable and brilliant.
| Property | Description |
|---|---|
| Mineral | Spinel |
| Chemical Formula | MgAl₂O₄ |
| Hardness (Mohs Scale) | 8 |
| Crystal System | Cubic |
| Refractive Index | 1.71 - 1.73 |
| Luster | Vitreous |
| Typical Colors | Red, pink, orange, purple, blue, black, colorless |
Its hardness of 8 on the Mohs scale makes it exceptionally durable and resistant to scratching, ideal for all forms of jewelry. The sources note that while red is the most popular and historically significant color, Spinel occurs in a wide array of colors, including vibrant pinks, oranges, and the coveted cobalt blue.
History and Lore
The history of Spinel is intrinsically linked to its role as a doppelgänger for ruby. This mistaken identity was so pervasive that it was not until modern gemology developed advanced testing methods that the distinction became clear. This long confusion, however, means that Spinel lacks a distinct ancient lore of its own, separate from that of ruby. The sources emphasize that Spinel was "underappreciated until recently," but today's consumers are increasingly drawn to it as a beautiful and more affordable alternative to ruby. Its addition to the birthstone list was a direct result of this renewed interest and its recognition as a fine gem in its own right.
Symbolism and Metaphysical Beliefs
Because of its recent elevation in status, Spinel's metaphysical beliefs are largely modern. It is often associated with revitalization and energy. The vibrant red and pink varieties are linked to passion and love, while the blue spinel is associated with calm and tranquility. Some believe it can help overcome lethargy and inspire a renewed sense of purpose. Its sparkle is seen as a reflection of inner light and joy.
Care and Cleaning
Spinel is an excellent gem for jewelry due to its durability. With a hardness of 8 and no cleavage, it is very resistant to damage. Cleaning is straightforward: it can be safely washed with warm soapy water and a brush. It is also stable under ultrasonic and steam cleaning, making it a low-maintenance choice for everyday wear.
Sardonyx: The Ancient Original
Sardonyx is the historical anchor of the August birthstones, with a lineage that stretches back to ancient civilizations. As a variety of onyx, it is characterized by its distinctive banding, which gives it a unique, earthy aesthetic.
Geological Formation and Origin
Sardonyx is a banded variety of chalcedony, which is a cryptocrystalline form of quartz. It is composed of alternating layers of sard (a reddish-brown variety of chalcedony) and onyx (a black and white banded variety). The bands are parallel and create a striking contrast. This gem forms in volcanic and metamorphic rocks and is found in locations such as India, Germany, and the United States.
Gemological Properties
As a member of the quartz family, Sardonyx has properties that are well-understood and consistent.
| Property | Description |
|---|---|
| Mineral | Chalcedony (Quartz) |
| Chemical Formula | SiO₂ |
| Hardness (Mohs Scale) | 7 |
| Crystal System | Trigonal (microcrystalline) |
| Refractive Index | 1.53 - 1.54 |
| Luster | Waxy to vitreous |
| Typical Colors | Bands of reddish-brown (sard) and black or white (onyx) |
Its hardness of 7 makes it durable enough for jewelry, including cameos and intaglios, for which it has been famously used. The luster is typically waxy but can be polished to a vitreous (glass-like) shine.
History and Lore
Sardonyx has a rich and storied past. It was the original August birthstone, with a history dating back more than 4,000 years. Ancient Romans prized it highly, setting it into rings and using it for seals. They believed the stone's red bands captured August's fiery energy while the white layers provided balance, making it a perfect symbol for the harvest month. Its name is derived from the Greek words sardios (sard) and onyx (onyx).
Beyond its Roman associations, Sardonyx was believed to bring courage, strength, and victory in battle. It was a popular talisman for protection and was often worn by soldiers. In later periods, it became a favored material for carving cameos, where the contrasting layers could be used to create intricate, multi-toned designs.
Symbolism and Metaphysical Beliefs
The symbolism of Sardonyx is tied to its banded appearance. It is seen as a stone of strength, protection, and stability. The red bands are associated with vitality and passion, while the white or black bands represent purity and grounding. It is believed to enhance willpower, discipline, and logical thinking. In some belief systems, it is thought to promote marital happiness and protect against negativity.
Care and Cleaning
Like Spinel, Sardonyx has a hardness of 7 and no cleavage, making it quite durable. It is resistant to everyday wear and tear. Cleaning is simple: use warm, soapy water and a soft brush. It can be safely cleaned with ultrasonic cleaners, but steam cleaning is not recommended due to the potential for fracture in any microscopic inclusions.
Conclusion
The August birthstones—Peridot, Spinel, and Sardonyx—offer a compelling narrative of geological wonder, historical depth, and evolving tradition. Each stone provides a distinct identity, catering to a wide range of aesthetic preferences and personal connections. Peridot, with its mantle-deep origins and solar lore, embodies the vibrant life of summer. Spinel, once mistaken for royalty, now claims its own throne as a durable and brilliant gem of many colors. Sardonyx, the ancient original, connects the modern wearer to millennia of human history, symbolizing strength and stability through its enduring bands.
Together, they represent one of the most versatile and historically layered selections in the entire birthstone calendar. For those born in August, this triad provides not just a single choice, but a spectrum of possibilities, each gem rich with stories and significance, ensuring that there is a perfect stone for every individual born in the heart of summer.