August is unique among the months of the year in that it is represented by three distinct birthstones: Peridot, Spinel, and Sardonyx. These gemstones, each with their own rich history, geological properties, and symbolic meanings, reflect the diverse character of August and its place in the world of gemology. The tradition of assigning gemstones to birth months is centuries old, with roots in biblical and ancient cultural practices. August’s trio of birthstones, however, was not established until more modern times, with additions and variations occurring over the centuries.
This article delves into the origins and evolution of August’s birthstones, their geological formation and properties, their symbolic and metaphysical associations, and practical considerations for their care and use in jewelry. Each stone—Peridot, Spinel, and Sardonyx—offers a unique glimpse into the interplay between nature, culture, and human history, making them not only beautiful but also deeply meaningful to those born in August.
History and Lore
The tradition of assigning gemstones to birth months is thought to have originated in the 15th century in Europe, though its roots can be traced back to ancient biblical texts. One of the earliest references is the Breastplate of Aaron, a sacred garment mentioned in the Hebrew Bible, which is said to have held 12 gemstones, each representing one of the 12 tribes of Israel. These stones were believed to have protective and spiritual powers. Over time, these biblical gems were associated with specific months of the year, forming the basis of the modern birthstone tradition.
August's three birthstones—Peridot, Spinel, and Sardonyx—each have their own historical significance.
Sardonyx is the earliest known August birthstone, with mentions in biblical texts and historical records. It was one of the foundation stones of New Jerusalem and a gem on the high priest’s Breastplate of Aaron. Sardonyx was highly valued in ancient times for its striated appearance, consisting of alternating bands of red sard and white onyx. This striking visual pattern made it a popular choice for seals, amulets, and religious artifacts. It was particularly favored in Roman and Egyptian cultures, where it was believed to offer protection and enhance self-control.
Peridot, on the other hand, gained prominence in the 19th and 20th centuries as it became the primary modern birthstone for August. The name "peridot" is of uncertain origin, though some sources suggest it may come from the Arabic word "faridat", meaning "gem." Peridot was once believed to be a form of topaz or emerald due to its green coloration, but it is now recognized as a distinct gemstone. Ancient cultures, including the Egyptians, held peridot in high regard, calling it the "gem of the sun" due to its vibrant green hue and association with light and life.
Spinel is the most recent of August’s birthstones, added to the list in the 20th century. For many years, spinel was mistaken for ruby and other red gemstones due to its vivid colors and similar physical properties. Once identified as a distinct species, spinel gained recognition for its brilliance and variety of colors, making it a popular choice for collectors and jewelers alike. The inclusion of spinel as an August birthstone reflects a growing appreciation for rarity, color diversity, and optical beauty in gemstones.
These three stones together reflect the evolving nature of the birthstone tradition, which continues to be influenced by historical, cultural, and geological discoveries.
Geological Formation and Sources
Each of August’s birthstones is formed under different geological conditions and is found in a variety of locations around the world.
Peridot
Peridot is one of the few gemstones formed deep within the Earth’s mantle, where it crystallizes over millions of years. It is often brought to the surface through volcanic activity, where it becomes embedded in basalt rock as magma cools. Peridot is also found in pallasite meteorites, where it forms in the presence of nickel-iron. The most significant sources of peridot include Zambia, Myanmar, the United States, and Egypt, with each location producing stones with slightly different color tones and clarity.
Peridot is a single-colored gemstone, with its green hue derived from iron content. The more iron present, the deeper the green color. Peridot is also known by the name olivine, a term derived from the olive-green color of the stone. Its formation process gives it a unique geological signature, making it one of the few gemstones that can be traced back to the Earth’s deep interior.
Spinel
Spinel forms in metamorphic and igneous rocks, typically in limestone-rich areas where heat and pressure cause the transformation of minerals. It is known for its wide range of colors, from deep red to blue, green, and even colorless, depending on trace elements like chromium and iron. High-quality spinel is most commonly found in Afghanistan, Burma, Sri Lanka, and Vietnam. The red spinels of Burma, in particular, are highly prized for their vibrant color and clarity.
Spinel is a hard gemstone, with a Mohs hardness of 8, making it durable and suitable for everyday wear. It is also known for its high refractive index, which gives it an exceptional brilliance and fire when cut and polished.
Sardonyx
Sardonyx is a banded form of chalcedony, a microcrystalline quartz that forms in sedimentary and metamorphic rocks. It is composed of alternating layers of sard (a reddish-brown chalcedony) and onyx (a white or black chalcedony). This banded structure gives sardonyx its distinctive striped appearance. Sardonyx is found in India, Brazil, Germany, the Czech Republic, Slovakia, Madagascar, Uruguay, and the United States.
The stone is relatively soft, with a Mohs hardness of 6.5 to 7, which means it requires careful handling to avoid scratches or chips. Despite its lower hardness, sardonyx is widely used in jewelry, particularly in pendants and carved pieces, where its banded pattern can be showcased effectively.
Gemological Properties
Each of August’s birthstones possesses distinct gemological properties that contribute to their beauty and durability.
Peridot
Peridot is a silicate mineral with the chemical formula Mg,Fe)₂(SiO₄). It is known for its hexagonal crystal structure, which contributes to its pleochroism—a property that allows it to show slightly different colors when viewed from different angles. Peridot has a Mohs hardness of 6.5 to 7, making it relatively durable but still susceptible to scratches and cleavage fractures. It has a refractive index ranging from 1.650 to 1.690, giving it a bright luster and a glassy appearance.
Peridot is not dichroic, meaning it does not display strong color changes under different lighting conditions. It is also not fluorescent, though it can exhibit a pale green fluorescence under UV light in some cases.
Spinel
Spinel is a oxide mineral with the chemical formula MgAl₂O₄. It has a cubic crystal structure, which gives it a high refractive index and a glassy luster. Spinel has a Mohs hardness of 8, making it one of the hardest of August’s birthstones and suitable for everyday wear in jewelry. Its refractive index ranges from 1.718 to 1.734, contributing to its brilliance and fire.
Spinel is known for its wide range of colors, which are caused by trace elements such as chromium, iron, and cobalt. The most valuable spinels are those with a deep red color, often referred to as "Burmese red." Spinel is also known for its lack of cleavage, making it resistant to chipping and breaking, even when cut into step or brilliant cuts.
Sardonyx
Sardonyx is a microcrystalline quartz with the chemical formula SiO₂. It is a banded chalcedony composed of layers of sard and onyx, giving it a distinctive striped appearance. Sardonyx has a Mohs hardness of 6.5 to 7, which is relatively soft compared to other gemstones, making it more prone to scratches and damage.
Sardonyx has a refractive index of 1.53 to 1.54, which is lower than that of peridot and spinel, giving it a subdued luster. It is not fluorescent, and its color is derived from iron and other impurities within the chalcedony.
Symbolism and Metaphysical Beliefs
Each of August’s birthstones carries its own set of symbolic and metaphysical associations, which have been passed down through history and continue to influence their use in jewelry and spiritual practices.
Peridot
Peridot has long been associated with positive energy, protection, and emotional healing. In ancient Egypt, it was believed to ward off nightmares and negative energies, and it was often used in amulets and protective charms. Peridot is also associated with growth, prosperity, and love, making it a popular choice for engagement rings and anniversary gifts.
Modern metaphysical beliefs associate peridot with inner strength, confidence, and emotional balance. It is believed to help reduce stress and anxiety, promote self-acceptance, and enhance creativity and focus. Peridot is also said to be a stone of transformation, helping individuals release old patterns and embrace new beginnings.
Spinel
Spinel is associated with passion, vitality, and emotional warmth. In ancient times, it was believed to have protective and healing properties, particularly for healing the heart and promoting love and compassion. Spinel is also said to enhance communication and self-expression, making it a popular choice for those seeking to improve their relationships.
Modern metaphysical beliefs associate spinel with energy, courage, and emotional resilience. It is believed to help individuals overcome fear and uncertainty, and to rekindle lost passion and motivation. Spinel is also associated with balance and harmony, making it a valuable stone for spiritual growth and emotional stability.
Sardonyx
Sardonyx has been used for centuries as a protective and grounding stone, particularly in ancient Roman and Egyptian cultures. It was believed to offer protection from negative energies, promote self-control and discipline, and enhance leadership and decision-making skills. Sardonyx was also used in seals and amulets, where it was believed to enhance authority and power.
Modern metaphysical beliefs associate sardonyx with clarity, focus, and emotional stability. It is believed to help individuals overcome fear and indecision, and to strengthen willpower and determination. Sardonyx is also associated with balance and harmony, making it a valuable stone for spiritual growth and emotional stability.
Care and Cleaning
Proper care and cleaning are essential for maintaining the beauty and longevity of August’s birthstones. Each stone has specific requirements due to its hardness, cleavage, and sensitivity to certain substances.
Peridot
Peridot has a Mohs hardness of 6.5 to 7, which means it is relatively durable but still susceptible to scratches and cleavage fractures. It should be stored separately from harder gemstones to avoid damage. Peridot should be cleaned with warm, soapy water and a soft cloth, avoiding ultrasonic or steam cleaners, which can cause internal fractures or damage.
Peridot is not resistant to acid, so it should be avoided contact with acidic substances such as vinegar or citrus-based cleaners. It should also be avoided exposure to extreme temperatures, as sudden temperature changes can cause cracking or thermal shock.
Spinel
Spinel has a Mohs hardness of 8, making it one of the hardest of August’s birthstones and suitable for everyday wear in jewelry. It is resistant to scratches and fractures, but it should still be stored separately from harder gemstones to avoid surface abrasion.
Spinel can be cleaned with warm, soapy water and a soft cloth, or with ultrasonic or steam cleaners, which are safe for most spinel varieties. It is not sensitive to acid or heat, making it more versatile in terms of cleaning and storage.
Sardonyx
Sardonyx has a Mohs hardness of 6.5 to 7, which means it is relatively soft and prone to scratches and damage. It should be stored separately from harder gemstones and avoided contact with abrasive materials.
Sardonyx can be cleaned with warm, soapy water and a soft cloth, but it should avoid ultrasonic or steam cleaners, which can cause internal damage or surface erosion. It is also not resistant to acid, so it should be avoided contact with acidic substances.
Conclusion
August’s birthstones—Peridot, Spinel, and Sardonyx—represent a rich and diverse tradition that spans centuries of historical, geological, and cultural significance. Each stone has its own unique properties, symbolism, and care requirements, making them not only beautiful but also deeply meaningful to those born in August. Whether used in jewelry, amulets, or spiritual practices, these gemstones continue to captivate and inspire, reflecting the beauty and complexity of the natural world and the enduring human fascination with gemstones.
From the deep green glow of peridot, the vibrant colors of spinel, and the striated patterns of sardonyx, August’s birthstones offer a rich tapestry of color, form, and meaning that continues to evolve with each generation.