August, a month synonymous with warmth and vitality, is represented by three distinct and captivating gemstones: peridot, spinel, and sardonyx. Each of these stones carries a unique history, a set of gemological properties, and a rich tapestry of symbolism and significance. Together, they form a compelling narrative of Earth’s geological processes and human cultural traditions.
This article delves into the properties, origins, and significance of these three August birthstones, offering an in-depth exploration of their roles in both historical and contemporary contexts. From their geological formation to their cultural and spiritual meanings, each stone tells a story that spans millennia. Whether you are a gemstone enthusiast, a jewelry buyer, or a student of gemology, this guide will provide a comprehensive understanding of the August birthstones.
History and Lore
The tradition of associating gemstones with birth months can be traced back to ancient times, with roots in religious and cultural practices. The earliest known references date back to the breastplate of the High Priest Aaron, as described in the Bible (Exodus 28:15–30). This breastplate was adorned with twelve gemstones, each representing one of the twelve tribes of Israel. While the exact identities of these stones remain debated, their symbolic role in connecting the divine with the earthly is clear.
Modern birthstone traditions began to take shape in the 19th and 20th centuries. The American National Association of Jewelers (now the Jewelers of America) and the American Gem Trade Association (now the Gemological Institute of America) played pivotal roles in standardizing the list of birthstones. In 1912, the first modern list of birthstones was established, and it has been updated over the years to reflect changes in gemstone availability and consumer preferences.
August is one of the few months with multiple birthstones. Initially, sardonyx was the sole August birthstone. However, due to its frequent confusion with peridot, peridot was added as a second birthstone. In 2016, spinel was introduced as the third August birthstone, reflecting a contemporary appreciation for the gemstone’s beauty and versatility.
The inclusion of multiple stones for August highlights the dynamic nature of birthstone traditions. These updates ensure that individuals have more options to choose from, especially when considering factors such as gemstone availability, affordability, and personal preference.
Geological Formation and Sources
Peridot
Peridot is a gem variety of the mineral olivine and is known for its vibrant yellow-green color. The stone’s formation is deeply tied to geological and cosmic processes. Peridot can be found in two distinct environments: within the Earth and beyond it. On Earth, peridot forms under extreme conditions in the Earth’s mantle, where it is brought to the surface through volcanic activity. Volcanic eruptions carry magma rich in olivine to the surface, where it cools and solidifies, forming peridot crystals.
Peridot is also found in meteorites, specifically in a type of meteorite known as pallasite. These meteorites are composed of nickel-iron and olivine, and they have traveled through space before landing on Earth. The presence of peridot in meteorites underscores its extraterrestrial origins, making it a truly celestial gemstone.
Significant sources of peridot include Arizona in the United States, where volcanic activity has left behind rich deposits. The San Carlos Apache Indian Reservation in Arizona is a well-known location for peridot mining. Another key source is Myanmar (formerly Burma), where the finest-quality peridot is found in the mountainous region near Mogok. Additionally, peridot can be found in countries such as Egypt, China, and Tanzania.
Spinel
Spinel is a mineral species that is often mistaken for ruby or sapphire due to its similar color and brilliance. However, spinel is a distinct mineral with its own unique properties. Spinel forms in metamorphic and igneous rocks, particularly in areas where there is high heat and pressure. The gemstone is composed of magnesium aluminum oxide and can exhibit a wide range of colors, including red, blue, pink, and even colorless.
Spinel is found in various parts of the world, including Myanmar, Sri Lanka, Afghanistan, and Tanzania. The gemstone’s historical significance is evident in the fact that some of the world’s most famous "rubies" are actually spinels. For example, the "Black Prince’s Ruby," set in the Imperial State Crown of the United Kingdom, is a large red spinel.
The addition of spinel as an August birthstone in 2016 reflects its growing popularity and recognition in the jewelry industry. Spinel’s affordability compared to rubies and sapphires, combined with its vibrant colors and durability, makes it an attractive option for those seeking a unique and meaningful gemstone.
Sardonyx
Sardonyx is a banded variety of chalcedony, a microcrystalline quartz. The stone is composed of alternating layers of sard (a reddish-brown to orange chalcedony) and onyx (a white or black chalcedony). Sardonyx forms in sedimentary and volcanic rocks, where it is deposited over time as layers of silica-rich water evaporates and leaves behind crystalline structures.
The banded appearance of sardonyx makes it ideal for carving and engraving. Historically, sardonyx was used in seals, signet rings, and cameos, particularly by the ancient Greeks and Romans. The stone was also one of the twelve stones on the High Priest’s breastplate, symbolizing the tribe of Judah.
Sardonyx is found in several parts of the world, including Brazil, India, Mexico, and the United States. The stone is relatively abundant, making it a more accessible option for jewelry and decorative items. Its durability and ability to hold intricate designs have contributed to its enduring popularity.
Gemological Properties
Peridot
Peridot is known for its distinctive yellow-green color, which is caused by the presence of iron in its composition. The gemstone has a refractive index ranging from 1.65 to 1.69 and a birefringence of 0.035 to 0.038. These properties contribute to peridot’s brilliance and clarity. The stone has a specific gravity of 3.34 and a hardness of 6.5 to 7 on the Mohs scale, making it relatively durable but not as hard as gems like diamonds or sapphires.
Peridot is available in a range of shades, from pale lime green to a richer olive color. The most valuable peridot stones are those with a deep, saturated color and high transparency. Due to its softness, peridot requires careful handling and should be protected from impacts and exposure to acidic substances.
Spinel
Spinel is a versatile gemstone that can exhibit a wide range of colors, including red, blue, pink, and colorless. The stone has a refractive index of 1.718 to 1.834 and a specific gravity of 3.6 to 4.1, depending on its composition. Spinel has a hardness of 8 on the Mohs scale, making it more durable than peridot but less hard than corundum (ruby and sapphire).
The gemstone’s brilliance and fire are enhanced by its high refractive index. Spinel is often cut in a variety of styles, including round, oval, and cushion cuts, to maximize its beauty. The stone is also known for its clarity, with many high-quality spinel specimens being free of inclusions.
Sardonyx
Sardonyx is a banded chalcedony that is composed of sard and onyx layers. The stone has a refractive index of 1.544 to 1.553 and a specific gravity of 2.60 to 2.65. Sardonyx has a hardness of 6.5 to 7 on the Mohs scale, making it durable enough for use in jewelry but still requiring care to avoid scratches.
The banded appearance of sardonyx is ideal for carving and engraving, making it a popular choice for cameos, intaglios, and seals. The stone’s colors can vary from reddish-brown to orange, with white or black onyx bands. This contrast enhances its visual appeal and makes it a versatile gemstone for various jewelry styles.
Symbolism and Metaphysical Beliefs
Each of the August birthstones carries its own set of symbolic meanings and metaphysical properties, reflecting the beliefs and traditions of different cultures throughout history.
Peridot
Peridot has long been associated with positivity, abundance, and protection. In ancient times, the gemstone was believed to have protective qualities and was used in amulets and talismans. The stone was thought to ward off nightmares and evil spirits, making it a popular choice for those seeking spiritual protection.
Peridot is also associated with prosperity and success. The gemstone is believed to enhance one’s ability to attract wealth and abundance, making it a favorable stone for those in business or seeking financial growth. Additionally, peridot is thought to promote emotional healing and balance, helping individuals release negative emotions and embrace a more positive outlook.
Spinel
Spinel is a gemstone of passion and energy. The stone is believed to enhance one’s vitality and enthusiasm, making it an ideal choice for those seeking motivation and inspiration. Spinel is also associated with love and relationships, and it is believed to promote harmony and understanding between partners.
In metaphysical practices, spinel is used to stimulate the root and heart chakras, promoting a sense of grounding and emotional stability. The gemstone is also believed to enhance one’s intuition and creativity, making it a valuable tool for those in artistic or spiritual pursuits.
Sardonyx
Sardonyx is a stone of strength, courage, and protection. The gemstone has been used historically in amulets and seals, particularly by the ancient Greeks and Romans, who believed it brought victory in battle and enhanced communication skills. Sardonyx is also associated with stability in relationships and is believed to promote open communication and trust between partners.
The stone is also believed to bring prosperity and good fortune, making it a popular choice for those in business or seeking financial success. Sardonyx is thought to enhance one’s ability to make sound decisions and to overcome obstacles with confidence and determination.
Care and Cleaning
Proper care and cleaning are essential for maintaining the beauty and longevity of August birthstone jewelry. Each gemstone has specific care requirements based on its hardness, composition, and sensitivity to environmental factors.
Peridot
Peridot has a hardness of 6.5 to 7 on the Mohs scale, making it relatively soft compared to other gemstones. The stone is vulnerable to damage from hard impacts and exposure to acidic substances, including acidic perspiration. Peridot should be protected from these conditions to prevent scratches and discoloration.
Cleaning peridot should be done with care. A soft-bristle brush and mild dish soap in warm water are recommended. Steam and ultrasonic cleaners should be avoided, as they can cause thermal shock and damage the stone. Peridot should be stored separately from harder gemstones to prevent scratching.
Spinel
Spinel has a hardness of 8 on the Mohs scale, making it more durable than peridot. The gemstone is generally resistant to scratches and is less sensitive to environmental factors. However, spinel should still be protected from hard impacts and exposure to harsh chemicals.
Cleaning spinel can be done with a soft-bristle brush and mild dish soap in warm water. Ultrasonic and steam cleaners are generally safe for spinel, but it is advisable to check with a professional jeweler to ensure the stone’s specific care requirements.
Spinel should be stored in a safe place, away from harder gemstones that could cause scratches. The stone’s durability makes it suitable for daily wear, but it is still important to handle it with care.
Sardonyx
Sardonyx has a hardness of 6.5 to 7 on the Mohs scale, making it durable enough for use in jewelry. The stone is relatively resistant to scratches and is not sensitive to environmental factors. However, sardonyx should still be protected from hard impacts and exposure to harsh chemicals.
Cleaning sardonyx can be done with a soft-bristle brush and mild dish soap in warm water. The stone can also be cleaned with ultrasonic or steam cleaners, but it is advisable to check with a professional jeweler to ensure the stone’s specific care requirements.
Sardonyx should be stored separately from harder gemstones to prevent scratching. The stone’s durability makes it suitable for daily wear, but it is still important to handle it with care.
Conclusion
The August birthstones—peridot, spinel, and sardonyx—each carry a unique history, set of gemological properties, and a rich tapestry of symbolism and significance. From their geological formation to their cultural and spiritual meanings, these stones offer a fascinating glimpse into the interplay between Earth’s natural processes and human traditions.
Peridot, with its extraterrestrial origins and vibrant green color, represents positivity, abundance, and protection. Spinel, often mistaken for ruby or sapphire, offers a vibrant and affordable alternative with its own unique charm and symbolism. Sardonyx, with its banded appearance and historical significance, is a stone of strength, courage, and protection.
Together, these three gemstones form a diverse and meaningful collection that reflects the dynamic nature of birthstone traditions. Whether used in jewelry, as decorative items, or for their metaphysical properties, the August birthstones continue to captivate and inspire those who wear them.