August, the eighth month of the year, is associated with three gemstones: Peridot, Spinel, and Sardonyx. While Peridot is the most widely recognized as the primary August birthstone, Spinel and Sardonyx also hold historical, spiritual, and aesthetic significance. These stones are not only prized for their beauty but also for their deep-rooted connections to history, mythology, and gemological science. This article explores the origins, properties, cultural symbolism, and practical considerations of these August birthstones, drawing from authoritative and historical sources.
Introduction
August is a month of vibrant energy and natural abundance. The birthstones associated with it reflect this vitality through their colors, properties, and historical relevance. Peridot, with its striking olive-green hue, has been admired since antiquity. Spinel, once mistaken for ruby, is gaining renewed appreciation for its brilliance and variety. Sardonyx, a striped chalcedony, carries layers of symbolic meaning and has been used in religious and royal contexts.
Each of these stones has a unique story to tell. They have been used in jewelry, religious artifacts, and even believed to possess metaphysical properties. Their journey from ancient times to modern collections is marked by scientific discovery, cultural exchange, and artistic expression.
This article will delve into the historical and geological context of each stone, explain their gemological properties, and explore the beliefs and traditions surrounding them. Additionally, we will provide practical advice on how to care for these gemstones, ensuring they retain their beauty for generations.
History and Lore
Peridot
Peridot has one of the longest histories among the August birthstones. Its name may derive from the Arabic word faridat, meaning “precious stone,” though its exact etymology remains uncertain. In ancient times, it was known as chrysolite, a term meaning “gold stone,” due to its golden-green color. It was sometimes confused with topaz or emerald, and in some cultures, it was considered more valuable than diamond.
Peridot was particularly revered in ancient Egypt, where it was mined from volcanic rocks on the island of Zabargad (St. John’s Island) in the Red Sea. This island was known as the only source of fine peridot for centuries and was considered sacred by the Egyptians. The gemstone was believed to ward off nightmares and negative energies. It was also used in jewelry and amulets, often carved into beads or set into rings.
In medieval Europe, peridot was associated with the sun and was thought to bring good fortune and protection. Some legends suggest that peridot was used in the construction of Solomon’s Temple, though this is more symbolic than historical. Today, peridot is the official birthstone for August and continues to be popular in jewelry, especially for those born in the month of August.
Spinel
Spinel is a relatively newer addition to the list of birthstones, officially recognized in the 20th century. However, its history is rich and complex. For centuries, red spinel was mistaken for ruby, and in fact, some of the most famous “rubies” in history are actually spinels. The most notable example is the Black Prince’s Ruby, a large red gemstone set in the Imperial State Crown of the United Kingdom. This stone, once owned by the Black Prince of Wales, was identified in the 18th century as a spinel, not a ruby.
Spinel was known as Balas ruby or rubicelle in earlier times. It was mined in regions such as Burma (now Myanmar) and Sri Lanka, where it was often found alongside ruby deposits. The confusion between the two stones was largely due to their similar appearance—both can have a deep red color and high brilliance. It wasn’t until the late 18th century that French mineralogist Jean-Baptiste Louis Romé de l’Isle conclusively identified spinel as a separate species from ruby. This distinction allowed spinel to be appreciated for its own unique qualities, and it has since become a popular gemstone in its own right.
Spinel comes in a wide range of colors, including red, pink, orange, yellow, green, blue, and even black. This versatility makes it a highly desirable gemstone for collectors and jewelers. In recent years, spinel has gained recognition not only as an August birthstone but also for its rarity and beauty.
Sardonyx
Sardonyx is one of the oldest August birthstones, with historical significance dating back to biblical times. It was mentioned in the Book of Exodus as one of the gemstones on the Breastplate of Aaron, the sacred garment of the high priest in the Jewish faith. This association with religious and spiritual power elevated the status of sardonyx in ancient times.
The name sardonyx comes from the Greek words sard (a type of red chalcedony) and onyx (a banded chalcedony). It is composed of alternating layers of red sard and white onyx, creating a distinctive striped pattern. This banded appearance made sardonyx a popular material for carving into seals, amulets, and cameos, especially in the Roman Empire.
Sardonyx was believed to have protective and purifying properties. In medieval Europe, it was used to ward off evil and was associated with courage and strength. It was also a favored gemstone in Renaissance jewelry, where it was often carved into intricate designs and set into pendants and rings. Today, sardonyx is considered an alternative or traditional August birthstone and is appreciated for its affordability and durability.
Geological Formation and Sources
Peridot
Peridot is a magnesium iron silicate mineral, with the chemical formula Mg₁₋ₓFeₓSiO₄, where x is typically between 0.04 and 0.18. It is formed in the Earth’s mantle and is brought to the surface through volcanic activity. Peridot is commonly found in igneous rocks such as basalt and peridotite. The finest-quality peridot is typically found in volcanic deposits, particularly on Zabargad Island in the Red Sea, as mentioned earlier.
Other notable sources of peridot include Arizona (USA), China, Brazil, and Myanmar. Arizona is particularly famous for its peridot deposits, where the gemstone is mined from basalt rock. The color of peridot ranges from yellow-green to olive-green, depending on the iron content. The more iron present, the deeper the green hue. Peridot is known for its transparency and glassy luster, and it is relatively easy to cut and polish.
Spinel
Spinel is a mineral composed of magnesium aluminum oxide, with the chemical formula MgAl₂O₄. It is formed in metamorphic and igneous rocks and is often found in association with corundum (ruby and sapphire). Spinel deposits are found in several countries, including Myanmar, Sri Lanka, Tanzania, Vietnam, and Madagascar.
The color of spinel varies widely due to different trace elements. For example, iron produces a red color, chromium a deep red or pink, and cobalt a blue or violet tone. The most valuable spinel stones are those with a pure, vivid color and high clarity. Spinel is relatively hard, with a Mohs hardness of 8, making it suitable for everyday wear in jewelry.
Sardonyx
Sardonyx is a type of chalcedony, a microcrystalline quartz mineral. It is composed of alternating layers of sard (a reddish chalcedony) and onyx (a banded chalcedony with white or black stripes). Sardonyx forms in sedimentary rocks and is often found in regions with volcanic activity. The most important sources of sardonyx include India, Brazil, Germany, the Czech Republic, Slovakia, Madagascar, Uruguay, and the United States.
Sardonyx is known for its durability and ease of carving, which makes it ideal for intricate designs. The red bands are caused by iron impurities, while the white or black bands are due to the absence of color. Sardonyx is a relatively affordable gemstone and is often used in pendants, rings, and other types of jewelry.
Gemological Properties
Peridot
Peridot is a relatively soft gemstone, with a Mohs hardness of 6.5 to 7. It is not as hard as diamond, ruby, or sapphire, but it is still durable enough for use in jewelry. Peridot is known for its refractive index, which ranges from 1.65 to 1.69, giving it a bright and lively appearance. It is also pleochroic, meaning it can display different colors when viewed from different angles—though this effect is subtle in most peridot stones.
Peridot is typically translucent to transparent, with a glassy to vitreous luster. It is found in a variety of shapes and cuts, including round, oval, and cushion cuts. Due to its softness, peridot should be cleaned with care and stored separately from harder gemstones to avoid scratches.
Spinel
Spinel is a harder gemstone, with a Mohs hardness of 8, making it suitable for everyday wear. It has a refractive index of 1.718 to 1.728, and its specific gravity ranges from 3.6 to 4.0, depending on the composition. Spinel is known for its brilliance and fire, especially in the red and pink varieties.
Spinel is available in a wide range of colors, and the color change variety is particularly rare and valuable. This type of spinel appears one color in daylight and changes to a different color under incandescent light. Spinel is also isotropic, meaning it does not exhibit double refraction, which makes it easier to cut and polish.
Sardonyx
Sardonyx has a Mohs hardness of 6.5 to 7, making it relatively durable for a chalcedony. It is translucent to opaque, with a waxy to vitreous luster. The refractive index of sardonyx is approximately 1.53 to 1.54, and it is uniaxial, meaning it has one optic axis.
Sardonyx is often cut into cabochons or cameos, where the banded patterns can be emphasized. It is also used in intaglio carvings, where the layers are used to create intricate designs. Sardonyx is relatively easy to clean and maintain, and it can be polished to a high shine.
Symbolism and Metaphysical Beliefs
Peridot
Peridot has long been associated with positive energy, protection, and emotional balance. In ancient Egypt, it was believed to ward off nightmares and bring good fortune. It was also used in religious and spiritual practices, often as a tool for divination and healing.
In modern times, peridot is associated with growth, prosperity, and renewal. It is believed to promote inner strength and confidence, making it a popular stone for those seeking to overcome challenges. Peridot is also considered a stone of love and loyalty, and it is often given as a gift to symbolize enduring relationships.
Spinel
Spinel is a relatively new player in the world of metaphysical gemstones, but it is gaining recognition for its emotional and spiritual properties. It is believed to enhance clarity of thought, emotional balance, and vitality. Red spinel, in particular, is associated with passion, courage, and vitality, making it a powerful stone for those seeking motivation and inspiration.
Spinel is also thought to have protective qualities, shielding the wearer from negative energies and promoting a sense of inner peace. It is a versatile stone that can be used in both personal and spiritual practices.
Sardonyx
Sardonyx has been used for its protective and purifying properties for centuries. In ancient times, it was believed to ward off evil spirits and promote courage and strength. It was also used in rituals and ceremonies, where it was thought to bring good fortune and success.
In modern metaphysical practices, sardonyx is associated with discipline, focus, and emotional stability. It is believed to help with overcoming fears and doubts, making it a popular stone for those seeking to build confidence and resilience. Sardonyx is also thought to promote honesty and integrity, making it a valuable stone for personal and professional growth.
Care and Cleaning
Proper care is essential to maintaining the beauty and longevity of August birthstones. Here are some guidelines for each gemstone:
Peridot
- Hardness: 6.5–7 on the Mohs scale.
- Cleaning: Use mild soap and warm water with a soft brush. Avoid ultrasonic cleaners and steamers, as they can damage the gemstone.
- Storage: Store peridot separately from harder gemstones to prevent scratches.
- Avoid: Exposure to harsh chemicals and prolonged heat.
Spinel
- Hardness: 8 on the Mohs scale.
- Cleaning: Spinel is more durable and can be cleaned with mild soap and warm water or ultrasonic cleaners.
- Storage: Store spinel in a soft cloth or padded container to prevent scratches.
- Avoid: Prolonged exposure to direct sunlight, which can cause some colors to fade.
Sardonyx
- Hardness: 6.5–7 on the Mohs scale.
- Cleaning: Sardonyx can be cleaned with mild soap and warm water. Avoid abrasive materials.
- Storage: Store sardonyx in a soft cloth or jewelry box to prevent scratches.
- Avoid: Exposure to harsh chemicals and excessive heat.
Conclusion
The August birthstones—Peridot, Spinel, and Sardonyx—represent a rich tapestry of history, geology, and cultural significance. Each stone carries a unique set of properties, from the vibrant green of peridot to the fiery red of spinel and the banded beauty of sardonyx. These gemstones have been valued for centuries, both for their aesthetic appeal and their symbolic meanings.
Whether you are choosing a birthstone for an August birthday or simply exploring the world of gemology, these stones offer a fascinating glimpse into the intersection of science, history, and human belief. Their journey from ancient times to modern collections is a testament to their enduring appeal and significance.
By understanding the properties, history, and symbolism of these August birthstones, we can appreciate them not only as beautiful gems but also as meaningful artifacts of our shared cultural heritage.