August boasts not one, but three recognized birthstones: peridot, spinel, and sardonyx. While peridot is often considered the primary August birthstone, spinel and sardonyx offer compelling alternatives, each with a unique history, geological origin, and symbolic meaning. This article will delve into the characteristics of each of these gemstones, exploring their historical significance, geological formation, gemological properties, and cultural associations, as understood through available sources.
History and Lore
Sardonyx holds the distinction of being the original birthstone for August, with a history stretching back over 4,000 years. Ancient civilizations valued this banded chalcedony for its perceived protective qualities. During the Renaissance, it was believed to aid public speakers, enhancing eloquence and persuasive ability. It was also thought to attract suitable partners for those seeking marriage and promote marital happiness.
Peridot’s history is often intertwined with that of emerald, as the two gems were frequently confused throughout much of history. The Red Sea island of Topazios, from which the name “topaz” is derived, was actually a significant source of peridot. Some historians speculate that stones identified as emeralds in Cleopatra’s famed collection were, in fact, peridot. The Shrine of the Three Holy Kings in Cologne Cathedral features 200 carats of gems once believed to be emeralds, now confirmed as peridot.
Spinel is the newest addition to the August birthstone family, only being officially recognized in 2016. However, its history is rich, albeit often overshadowed by its resemblance to ruby. For centuries, red spinel was mistaken for ruby, particularly in historical jewelry and royal collections. Spinel is traditionally associated with 22nd wedding anniversaries.
Geological Formation and Sources
The formation of these three birthstones occurs through vastly different geological processes. Peridot is formed under extreme conditions, originating in the Earth’s mantle and brought to the surface through volcanic activity. It can also be found within meteorites, specifically Pallasite Meteorites, though these typically yield stones too small for jewelry use.
Sardonyx, a variety of chalcedony, is formed through the layering of sard and onyx, resulting in its distinctive banded appearance. Major production of sardonyx occurs in India, with additional sources in Brazil, Germany, Czechoslovakia, Madagascar, Uruguay, and the United States.
Spinel crystallizes in metamorphic rocks and alluvial deposits. Significant sources include Tajikistan, Myanmar, Sri Lanka, Vietnam, Tanzania, and Pakistan. Myanmar is particularly renowned for producing spinel in vibrant shades of red and pink. Sri Lanka yields blue, pink, and purple spinel, often found in the country’s central highlands and river gravels. Vietnam’s Luc Yen region is known for deep red, purple, pink, vivid blue, and violet-blue spinel. Tanzania has also emerged as a source of pinkish and orangy-red spinel since 2007.
Gemological Properties
Peridot is the gem variety of the mineral olivine, with a chemical formula of (Mg,Fe)2 SiO4. Its color ranges from yellowish-green to greenish-yellow, with the most desirable stones exhibiting a lime green or olive hue. The presence of iron within its composition is responsible for its characteristic color. Peridot is sometimes referred to as the “evening emerald” due to its ability to sparkle under both natural and artificial light.
Sardonyx is a composite gemstone, formed from layers of sard (a reddish-brown chalcedony) and onyx (typically white or black). Its appearance is characterized by bands of reddish-brown to dark orange alternating with white or black layers.
Spinel is a distinct mineral species with a different crystal structure than ruby or sapphire, despite often being mistaken for them. It occurs in a wide range of colors, including intense red, vivid pink, orange, purple, violet, blue, and bluish-green.
| Gemstone | Chemical Formula | Color Range |
|---|---|---|
| Peridot | (Mg,Fe)2 SiO4 | Yellowish-green to greenish-yellow |
| Sardonyx | Mixture of Chalcedony | Reddish-brown to dark orange with white/black bands |
| Spinel | Various (Mg,Fe,Zn,etc.) | Red, pink, orange, purple, violet, blue, bluish-green |
Symbolism and Metaphysical Beliefs
Throughout history, these August birthstones have been attributed with various symbolic meanings and metaphysical properties. Peridot has been associated with abundance, protection, and positivity. During the Renaissance, it was believed to enhance eloquence and attract love.
Sardonyx symbolizes strength, courage, and protection. Ancient Greeks and Romans used it in amulets, cameos, and seals, believing it brought victory in battle and improved communication skills.
Spinel, while a more recent addition to the birthstone list, is associated with revitalization and hope. Its vibrant colors are thought to inspire passion and creativity.
Care and Cleaning
The durability and care requirements of these gemstones vary based on their hardness and other properties. Peridot, being relatively softer than some other gems, requires careful handling to avoid scratches and damage.
Sardonyx, being a form of chalcedony, is relatively durable and can withstand normal wear.
Spinel is a durable gemstone suitable for everyday wear. However, like all jewelry, it should be protected from harsh chemicals and extreme temperatures.
General cleaning for all three stones involves using warm, soapy water and a soft brush. Avoid ultrasonic cleaners, as they may damage some gemstones.
Conclusion
August’s birthstones – peridot, spinel, and sardonyx – represent a diverse and fascinating collection of gemstones. From the ancient origins of sardonyx to the volcanic birth of peridot and the historically confused identity of spinel, each stone carries a unique story. Their varied colors, geological formations, and symbolic meanings offer a wealth of choice for those born in August, or for anyone seeking a gemstone with a rich history and captivating beauty.