For those born in August, the month is graced with the unique privilege of having not one, but three official birthstones: peridot, sardonyx, and spinel. Each of these gems carries its own rich history, distinct gemological properties, and deep cultural significance. Whether celebrated for their beauty, symbolism, or geological rarity, August birthstones offer a compelling range of options for jewelry and personal adornment.
This article delves into the origins, meanings, and scientific attributes of each of these gemstones, drawing from historical accounts, geological data, and modern designations. From the fiery reds of spinel to the golden-green glow of peridot and the banded elegance of sardonyx, the August birthstones reflect a blend of tradition, innovation, and aesthetic appeal.
Introduction
The August birthstones—peridot, sardonyx, and spinel—are among the most diverse and historically rich gemstones in the birthstone calendar. Each stone has a unique place in both ancient lore and modern gemology. Sardonyx, the oldest designated August birthstone, has been cherished since antiquity for its contrasting bands of red and white. Peridot, with its vibrant green hue, has been found in volcanic regions and has long been associated with the sun and good fortune. Spinel, the newest addition to the August birthstone list, was officially recognized in 2016, owing to its dazzling colors and historical confusion with ruby and sapphire.
This article explores the geological properties, historical significance, cultural symbolism, and modern relevance of each of these August birthstones. It also includes practical advice on care and cleaning, and highlights the importance of each stone in contemporary jewelry design and personal collections.
History and Lore
Sardonyx: The Ancient August Birthstone
Sardonyx is the oldest of the August birthstones, with a history that stretches back to ancient civilizations. Composed of two types of chalcedony—sard and onyx—sardonyx is characterized by alternating bands of brownish-red sard and white or black onyx. These distinct layers have made it a popular material for seals, rings, and other ornamental items.
In ancient Rome, sardonyx was widely used for seals and signet rings, and Roman soldiers believed the stone brought good luck and protection in battle. The stone was also associated with orators and public speakers, who wore it to enhance their eloquence during the Renaissance. In ancient Egypt and Greece, sardonyx was worn as part of various jewelry pieces, including rings, bracelets, earrings, and lockets.
One of the most notable historical references to sardonyx appears in the Old Testament, where it is believed to have been one of the stones embedded in the High Priest’s breastplate. This religious association further elevated the stone’s status and significance in ancient times.
Today, sardonyx is still valued for its symbolic meanings, representing spirituality, open communication, prosperity, courage, and healthy relationships. It remains a meaningful gemstone in modern jewelry, especially in vintage and artisanal designs.
Peridot: The Sun’s Gift to August
Peridot is one of the most recognizable August birthstones, known for its vibrant green color, which ranges from yellow-green to deep olive. The name "peridot" is derived from the Arabic word "fadat," meaning "gem," and also has Greek origins, where it means "to give plenty."
Peridot is formed deep within the Earth, often found in volcanic rocks, and is brought to the surface through tectonic activity. Some of the most notable sources include Egypt, where the Egyptians referred to peridot as the "Gem of the Sun." The stone was believed to bring confidence, power, good health, and good fortune, and was often used in pharaohs’ tombs to protect against the evil eye.
Another significant source of peridot is Hawaii, particularly on the island of Oahu, where Papakolea Beach is known for its green-hued sand, which is rich in crushed olivine—a mineral form of peridot. Ancient Egyptians closely guarded the island of Zabargad, off the coast of Egypt, as it was a primary source of high-quality peridot.
Historically, peridot was also mistaken for emerald, and some of Cleopatra’s famous emeralds were actually peridots. In modern times, peridot is especially popular in jewelry for August birthdays and is also a traditional gift for the 16th wedding anniversary.
Spinel: The Modern Addition to August
Spinel is the newest addition to the August birthstone list, officially designated in 2016 by the American Gem Trade Association (AGTA) and the Jewelers of America (JA). Despite its recent recognition, spinel has a long and fascinating history that spans across centuries and continents.
Spinel is a silicate mineral that comes in a wide range of colors, including red, pink, orange, yellow, green, blue, and purple. The name "spinel" comes from the Latin word "spina," meaning "thorn," likely due to the gemstone’s crystal habit.
Spinel has often been mistaken for other gemstones, particularly ruby and sapphire, due to its similar appearance and refractive properties. For example, many 14th-century Spanish kings wore what they believed to be rubies, only to discover centuries later that the stones were actually spinel. This misidentification persisted for a long time due to the similar red color and brilliance.
Spinel is also known by several nickname-like names, such as "rubicelle" for yellow-orange spinel, "almandine" for purple spinel, and "sapphirine" for blue spinel. This variety of colors and names highlights the gemstone’s versatility and regal appeal.
The stone was historically known as the "immortality gemstone," and was believed to bring longevity and vitality. In modern times, spinel is celebrated for its rare colors and brilliance, and is often used in high-end jewelry, including engagement rings, earrings, and pendants.
Geological Formation and Sources
Sardonyx
Sardonyx is a banded variety of chalcedony, a type of microcrystalline quartz. It forms through sedimentary and hydrothermal processes, where silica-rich water deposits layers of different-colored chalcedony over time.
The main source of sardonyx is India, which produces stones with strong contrast between the red and white/onyx layers. Other notable sources include Brazil, Germany, Czechoslovakia, Madagascar, Uruguay, and the United States.
The distinct banding of sardonyx is what gives it its aesthetic appeal, and the stone is often carved into intaglios, cameos, and seals. The red bands are formed from sard, a type of chalcedony with a reddish-brown color, while the white or black bands are onyx, a form of chalcedony with a pale or dark color.
Peridot
Peridot is a nepheline olivine, a silicate mineral that forms in mafic and ultramafic igneous rocks. It is commonly found in volcanic regions, where it is brought to the surface through tectonic and volcanic activity.
The most notable sources of peridot include:
- Egypt: The ancient Egyptians mined peridot from the island of Zabargad, located in the Red Sea. This was one of the earliest and most important sources.
- Hawaii: The green sand of Papakolea Beach on the island of Oahu is rich in peridot crystals, which are brought to the surface through volcanic activity.
- Pakistan: Peridot from Pakistan is considered rare and valuable, often rivaling or exceeding diamonds in value.
Peridot is relatively hard and has a Mohs hardness of 6.5–7, making it suitable for everyday wear in jewelry. It is also thermally stable, which makes it ideal for heat-setting in jewelry.
Spinel
Spinel is a garnet-like mineral with a wide range of colors, from red and pink to blue, green, and yellow. It forms in metamorphic and igneous rocks, and is often found in alluvial deposits.
The main sources of spinel include:
- Myanmar: Known for producing intense red and pink spinels, some of the most valuable and sought-after.
- Sri Lanka: Famous for blue, pink, and purple spinels, especially from the Central Highlands and Ratnapura District.
- Vietnam: The Luc Yen region in northern Vietnam is known for deep red, purple, and blue spinels.
- Tanzania: In 2007, pinkish and orangy-red spinels were discovered in Tanzania, adding to the stone’s global appeal.
- Pakistan: Another significant source, especially for red and pink spinels.
Spinel has a Mohs hardness of 8, making it durable and suitable for everyday wear. It also has a high refractive index, which gives it a brilliant, glassy luster.
Gemological Properties
| Gemstone | Color | Hardness (Mohs) | Chemical Formula | Origin | Cut | Clarity | Refractive Index |
|---|---|---|---|---|---|---|---|
| Peridot | Yellow-green to olive | 6.5–7 | Mg₁.₈Fe₀.₂SiO₄ | Egypt, Hawaii, Pakistan | Typically cut as a brilliant or mixed cut | Usually clear to slightly included | 1.654–1.688 |
| Sardonyx | Banded red and white/onyx | 6.5–7 | SiO₂ (Chalcedony) | India, Brazil, USA | Cabochon, intaglio, cameo | Usually clear to slightly included | 1.486–1.530 |
| Spinel | Red, pink, blue, green, etc. | 8 | MgAl₂O₄ | Myanmar, Sri Lanka, Vietnam | Brilliant, round, oval, princess | Usually clear to slightly included | 1.718–1.730 |
Peridot
- Color: Peridot is known for its yellow-green to olive-green color, caused by the presence of iron (Fe) in its chemical structure.
- Hardness: With a Mohs hardness of 6.5–7, peridot is relatively hard, but not as hard as diamond or ruby.
- Chemical Formula: Peridot has the chemical formula Mg₁.₈Fe₀.₂SiO₄, and is a member of the olivine mineral group.
- Clarity: Peridot is often included, especially in Hawaiian and Egyptian sources, but the inclusions are usually not detrimental to its beauty.
- Refractive Index: Peridot has a refractive index of 1.654–1.688, which gives it a vibrant, glassy luster.
Sardonyx
- Color: Sardonyx is banded, with red and white or onyx layers.
- Hardness: With a Mohs hardness of 6.5–7, sardonyx is moderately hard, suitable for everyday wear.
- Chemical Formula: Sardonyx is a type of chalcedony, with the chemical formula SiO₂.
- Clarity: Sardonyx is usually clear, though it may contain minor inclusions.
- Refractive Index: The refractive index of sardonyx ranges from 1.486–1.530.
Spinel
- Color: Spinel comes in a wide range of colors, including red, pink, blue, green, yellow, and purple.
- Hardness: Spinel has a Mohs hardness of 8, making it durable and suitable for everyday wear.
- Chemical Formula: Spinel has the chemical formula MgAl₂O₄, and is a silicate mineral.
- Clarity: Spinel is often very clear, with few inclusions, especially in Myanmar and Sri Lankan sources.
- Refractive Index: Spinel has a refractive index of 1.718–1.730, which gives it a brilliant, glassy luster.
Symbolism and Metaphysical Beliefs
Sardonyx
Sardonyx has long been associated with prosperity, courage, and communication. In ancient Rome, it was believed to enhance eloquence, and was worn by orators and public speakers to improve their ability to express themselves.
The stone was also associated with good luck and protection, especially in battle and warfare. Roman soldiers wore sardonyx rings and amulets to ward off misfortune and ensure victory.
In ancient Egypt and Greece, sardonyx was used in jewelry and talismans to promote spiritual growth, harmony in relationships, and overall well-being.
Modern interpretations of sardonyx continue to emphasize its symbolism of spiritual growth, communication, and emotional balance.
Peridot
Peridot has long been associated with the sun, and was believed to radiate positive energy and good fortune. In ancient Egypt, peridot was known as the "Gem of the Sun," and was believed to bring confidence, power, and health to its wearer.
The stone was also believed to ward off nightmares and negative thoughts, and was used in pharaohs’ tombs to protect against the evil eye.
In modern times, peridot is believed to bring joy, optimism, and emotional healing. It is also associated with new beginnings and personal growth, making it a popular choice for birthstone jewelry.
Spinel
Spinel has been associated with longevity, vitality, and immortality, and was historically known as the "immortality gemstone." The stone was believed to enhance vitality and strength, and was worn by kings and rulers to maintain their health and energy.
Spinel is also believed to enhance emotional stability, courage, and confidence, and is often used in spiritual and meditative practices.
Due to its brilliant colors and regal appearance, spinel is also associated with luxury, elegance, and beauty.
Care and Cleaning
Peridot
- Hardness: Peridot has a Mohs hardness of 6.5–7, which means it is relatively hard, but still prone to scratches and abrasions.
- Cleavage: Peridot has no cleavage, but it is susceptible to chipping, especially if struck at an angle.
- Cleaning: Peridot can be cleaned with a soft brush, warm soapy water, and a gentle cloth. Avoid ultrasonic and steam cleaners, as these can cause damage.
- Storage: Store peridot separately from harder gemstones to avoid scratches.
Sardonyx
- Hardness: Sardonyx has a Mohs hardness of 6.5–7, making it suitable for everyday wear.
- Cleavage: Sardonyx has no cleavage, but it is susceptible to chipping, especially if it is cut as a cabochon or cameo.
- Cleaning: Sardonyx can be cleaned with a soft brush, warm soapy water, and a gentle cloth. Avoid ultrasonic and steam cleaners, as these can damage the stone.
- Storage: Store sardonyx separately from harder gemstones to avoid scratches.
Spinel
- Hardness: Spinel has a Mohs hardness of 8, making it very durable and suitable for everyday wear.
- Cleavage: Spinel has no cleavage, making it less prone to chipping and cracking.
- Cleaning: Spinel can be cleaned with a soft brush, warm soapy water, and a gentle cloth. It is also safe to use ultrasonic and steam cleaners.
- Storage: Spinel can be stored with other gemstones, as it is not prone to scratches or chipping.
Conclusion
The August birthstones—peridot, sardonyx, and spinel—represent a rich tapestry of history, beauty, and symbolism. Each of these gemstones has its own distinct origin, gemological properties, and cultural significance, making them unique and valuable additions to any jewelry collection.
From the banded elegance of sardonyx to the radiant green of peridot and the brilliant colors of spinel, August birthstones offer a diverse range of options for jewelry design and personal expression. Whether worn for aesthetic appeal, symbolic meaning, or spiritual significance, these gemstones continue to capture the imagination and admiration of gemstone enthusiasts around the world.
As the only month with three official birthstones, August stands out in the birthstone calendar, offering a versatile and meaningful choice for those born in this month. Whether used in engagement rings, earrings, necklaces, or pendants, August birthstone jewelry is a celebration of beauty, history, and personal significance.