The month of August is uniquely represented by two distinct and captivating birthstones: the vibrant green Peridot and the versatile Spinel. While Peridot stands as the traditional and primary stone, Spinel has been officially recognized as a modern co birthstone, offering a spectrum of colors that includes the coveted red variety often mistaken for ruby. Together, they embody the warmth of late summer and possess rich histories, unique gemological properties, and deep symbolic meanings. This article provides a comprehensive exploration of these two gems, detailing their geological origins, physical characteristics, historical lore, and practical care, drawing exclusively from authoritative sources to present an expert overview for gemstone enthusiasts and collectors.
History and Lore
The history of August's birthstones is a tale of two gems with vastly different pasts. Peridot is one of the oldest known gemstones, with a history stretching back thousands of years. Ancient civilizations revered this vibrant green stone, imbuing it with protective and divine powers. In Ancient Egypt, peridot was known as "the gem of the sun," a title that reflects its radiant color and its perceived connection to the sun god, Ra. It was believed to offer protection from nightmares and evil spirits, and its use in jewelry was common among both royalty and commoners. The Egyptians mined peridot on the island of Zabargad in the Red Sea, a source that supplied the world with this gem for centuries.
Beyond Egypt, peridot was also a symbol of friendship and was believed to bring good luck and happiness to its wearer. Its lore extends to the islands of Hawaii, where local legend holds that peridot stones are the tears of the goddess Pele, the creator of the volcanic landscapes. This connection to nature and elemental forces highlights the stone's long-standing association with vitality and life force.
Spinel, on the other hand, has a more complex history, largely defined by its frequent confusion with other, more famous gemstones. For centuries, the magnificent red spinels from Central Asia—particularly the legendary "Black Prince's Ruby" embedded in the British Imperial State Crown—were mistaken for rubies. This misidentification, while a testament to spinel's beauty, meant that it often lived in the shadow of its "precious" counterpart. However, spinel itself has been treasured in its own right, particularly in the Mughal Empire and in Southeast Asia, where large, flawless crystals were highly prized. It was only in the 19th century that gemologists were able to definitively distinguish spinel from ruby based on differences in their chemical composition and crystal structure. The official recognition of spinel as a birthstone for August in 2016 by the American Gem Trade Association and Jewelers of America solidified its status as a gem worthy of its own acclaim.
Geological Formation and Sources
The distinct chemical compositions of Peridot and Spinel lead them to form in very different geological environments. Peridot is a variety of the mineral olivine, a magnesium iron silicate. Its formation occurs deep within the Earth's mantle, and it is brought to the surface through volcanic activity. This igneous origin is why peridot is often found in volcanic rock and is considered a gemstone of the earth's fiery heart. Its signature green color is caused by the presence of iron within its crystal structure. The intensity and shade of the green depend on the amount of iron present.
Historically, the most significant source of peridot was the island of Zabargad in the Red Sea, which was the primary source for ancient Egyptian and Roman gemstones. While this mine is no longer a major producer, peridot is currently mined in various locations around the world. Notable modern sources include Pakistan, which is famous for producing large, high-quality peridots with a rich olive-green color, as well as the United States (Arizona), China, Myanmar, and Vietnam.
Spinel is a magnesium aluminum oxide, making it an oxide mineral, fundamentally different from peridot's silicate structure. It forms under high-temperature and low-pressure conditions in metamorphic rocks, such as marble, and also in alluvial deposits. This dual formation process allows for the creation of beautiful crystals in a wide array of colors.
For centuries, the most prized red spinels came from the Badakhshan region of Central Asia (modern-day Afghanistan and Tajikistan). These mines produced the large, transparent red stones that were so often confused with rubies. Today, spinel is sourced from several locations, including Sri Lanka, which is known for producing a variety of colors, and Vietnam, which has emerged as a source for vibrant pink and red spinels. Other sources include Tanzania, Nigeria, and Myanmar, each contributing to the global supply of this diverse gem.
Gemological Properties
While both are birthstones for August, Peridot and Spinel possess distinct physical and chemical characteristics that define their appearance and durability.
Peridot
Peridot is celebrated for its unique olive-green hue, a color that is consistent throughout the gem and not typically subject to pleochroism (the display of different colors from different angles). Its appeal lies in its consistent and lively color.
- Chemical Composition: (Mg, Fe)₂SiO₄ (Magnesium Iron Silicate)
- Hardness: 6.5 to 7 on the Mohs scale. This makes it moderately durable, but it is susceptible to scratching if not handled with care. It is better suited for jewelry that is less likely to experience impact, such as pendants and earrings.
- Crystal System: Orthorhombic
- Refractive Index: 1.65 to 1.69
- Luster: Vitreous (glass-like)
- Special Properties: Peridot exhibits a high double refraction, which can be observed with a loupe, causing the back facets of the gem to appear doubled.
Spinel
Spinel is prized for its exceptional hardness and the sheer breadth of its color palette. It is a highly durable gemstone, making it suitable for all types of jewelry, including rings.
- Chemical Composition: MgAl₂O₄ (Magnesium Aluminum Oxide)
- Hardness: 8 on the Mohs scale. This superior hardness makes spinel much more resistant to scratching and wear than peridot.
- Crystal System: Cubic
- Refractive Index: 1.71 to 1.73
- Luster: Vitreous (glass-like)
- Special Properties: Spinel can appear in a rainbow of colors, including red, pink, blue, violet, and black. The red variety is the most sought-after, but the cobalt blue spinel is also exceptionally valuable. It is generally clean and transparent, with fewer inclusions than many other colored gemstones.
| Property | Peridot | Spinel |
|---|---|---|
| Chemical Family | Silicate (Olivine) | Oxide |
| Hardness (Mohs) | 6.5 - 7 | 8 |
| Primary Colors | Olive-green, yellowish-green | Red, pink, blue, black, violet |
| Key Feature | Consistent green color, high double refraction | Wide color range, exceptional durability |
| Best Use in Jewelry | Pendants, Earrings | All types, including rings |
Symbolism and Metaphysical Beliefs
Across cultures and centuries, both Peridot and Spinel have been attributed with a range of symbolic meanings and metaphysical properties.
Peridot's bright, green energy is consistently linked to themes of healing, protection, and vitality. Its historical role as a protective talisman for travelers and warriors underscores its perceived power to ward off negativity and harm. The association with the sun in Ancient Egypt connects it to warmth, life, and positive energy. In modern metaphysical beliefs, peridot is considered a stone of renewal and growth, helping to cleanse and rejuvenate the body and spirit. It is often called the "stone of compassion," believed to bring warmth and understanding to relationships and to promote friendship and happiness.
Spinel's symbolism is as varied as its colors. Red spinel, due to its long confusion with ruby, inherited much of the lore associated with that stone, including connections to passion, energy, and life force. However, spinel has also developed its own identity as a stone of renewal and revitalization. It is believed to help overcome lethargy and inject new energy into one's life. The wide range of spinel colors allows for a broader spectrum of symbolic associations; for example, blue spinel is linked to wisdom and communication, while pink spinel is connected to love and compassion. Overall, spinel is seen as a stone that can help one achieve their goals and find a sense of harmony and balance.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of these gemstones, and the differences in their hardness directly impact the recommended handling and cleaning methods.
Peridot, with its moderate hardness of 6.5 to 7, requires gentle care. It should be protected from hard knocks and abrasive materials. To clean peridot, use warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaners, as the heat and vibrations can cause fractures in the stone. It is also advisable to keep peridot away from harsh chemicals, including household cleaners and cosmetics, which can dull its surface.
Spinel, ranking an 8 on the Mohs scale, is considerably more durable and resilient. It can be cleaned using the same method as peridot—warm, soapy water and a soft brush—but it is also generally safe for use in ultrasonic cleaners. However, it is always best to exercise caution with any valuable gemstone. Spinel's hardness makes it an excellent choice for rings and other jewelry that is worn daily, as it is less prone to scratching and damage.
Conclusion
Peridot and Spinel, the two birthstones of August, offer a compelling study in contrasts. Peridot, the ancient "gem of the sun," is a singular, vibrant green stone born from the volcanic heart of the Earth, revered for its protective qualities and connection to life and friendship. Spinel, a more modern addition to the birthstone family, is a marvel of durability and diversity, presenting a spectrum of colors that has captivated humanity for centuries, often in the shadow of other gems but now stepping into its own light. While Peridot must be handled with care due to its relative softness, Spinel offers superior toughness suitable for any setting. Together, they provide August-born individuals with a choice between a timeless, radiant green and a brilliant, versatile array of colors, each with a deep history and a unique place in the world of gemology.