October boasts not one, but two recognized birthstones: the captivating opal and the vibrant tourmaline. Both gems offer a stunning spectrum of colors and a rich history, making them cherished adornments for centuries. This article delves into the origins, properties, and significance of these October birthstones, drawing upon available knowledge to provide a comprehensive overview for enthusiasts and students of gemology.
History and Lore
The opal, the traditional October birthstone, carries a legacy steeped in ancient beliefs and captivating tales. Its name is believed to originate from the Sanskrit word upala, meaning “precious stone,” which transitioned to opalus in ancient Rome. Throughout history, the opal has inspired diverse interpretations. Ancient Bedouins believed opals held lightning and descended from the sky during thunderstorms, while ancient Greeks associated the gem with the gift of prophecy and protection from illness. Europeans once considered opal a symbol of purity, hope, and truth, believing it embodied the virtues of all colored stones.
Tourmaline, the more recently adopted October birthstone, derives its name from the Sinhalese word toramalli, meaning “stone with mixed colors.” This name aptly describes the gem’s remarkable ability to exhibit multiple hues within a single crystal. Ancient mystics believed tourmaline could inspire artistic expression, perhaps due to its diverse and inspiring color palette.
Geological Formation and Sources
Australia currently dominates the global opal market, serving as the most productive source for this October birthstone. Within Australia, specific regions yield distinct opal varieties. Lightning Ridge, in New South Wales, is renowned for its prized black opal. White opal is found in the White Cliffs area of New South Wales, as well as in Mintabie, Andamooka, and Coober Pedy in South Australia. Boulder opal, unique to Queensland, is also sourced from this country.
Beyond Australia, opal deposits are found in Ethiopia, Mexico, and Brazil, as well as in Central Europe, Honduras, Indonesia, Madagascar, Peru, Turkey, and the United States. In Ethiopia, opal is mined near Wegel Tena, in Wollo Province, with gems exhibiting a range of body colors, including white, yellow, orange, brownish red, and “chocolate” brown, some displaying play-of-color. Another Ethiopian mine, in Shewa Province, yields black opal alongside orange, white, and crystal opal. Mexico’s Querétero state is known for its fire opal, showcasing yellow, orange, and reddish-orange to red hues, some with notable play-of-color.
Gemological Properties
Opal’s defining characteristic is its “play-of-color,” a shifting display of rainbow hues. This phenomenon is caused by the diffraction of light as it passes through microscopic silica spheres within the gem. Opal typically ranges from 5 to 6.5 on the Mohs scale of hardness, making it relatively softer than many other gemstones. This lower hardness necessitates careful handling and storage to prevent scratching. Opal may be treated through impregnation with oil, wax, or plastic to enhance its appearance. Opal doublets and triplets, constructed from slices of opal glued to a base material and covered with a quartz dome, are also common.
Tourmaline, the newer October birthstone, is celebrated for its dazzling array of colors. Popular varieties include pink and red rubellites, emerald green “chrome” tourmalines, and neon green and blue-to-violet “paraíba” tourmalines. The name itself reflects this characteristic, meaning “stone with mixed colors.” While the provided sources do not specify the hardness of tourmaline, it is generally known to be a relatively durable gemstone.
Symbolism and Metaphysical Beliefs
Throughout history, both opal and tourmaline have been attributed with symbolic meanings and metaphysical properties. As previously mentioned, opal was historically believed to embody the virtues of all colored stones, representing purity, hope, and truth. It is also the traditional stone given to celebrate the 14th wedding anniversary.
Tourmaline’s association with artistic inspiration stems from its diverse color palette, believed to stimulate creativity and emotional expression. While the sources do not elaborate on specific metaphysical beliefs surrounding tourmaline, its vibrant colors likely contributed to its perceived powers in various cultures.
Care and Cleaning
Proper care is essential to maintain the beauty of both opal and tourmaline. Opal, due to its lower hardness, should be stored separately from harder gemstones like diamonds, rubies, sapphires, and emeralds to prevent scratching. Cleaning opal is best achieved with warm, soapy water, avoiding harsh chemicals or abrasive materials. Prolonged exposure to water should be avoided, particularly for opal doublets and triplets, as it can weaken the adhesive. Opal should also be protected from high heat and sudden temperature changes, which can cause fracturing.
While specific cleaning instructions for tourmaline are not provided in the sources, its generally greater durability suggests it can withstand more robust cleaning methods. However, it is always advisable to use gentle cleaning solutions and avoid harsh chemicals.
Fashion Jewelry Considerations
The sources mention that fashion jewelry is often plated with 14K gold or rhodium over brass. To protect the plating and prevent tarnish, it is recommended to remove such jewelry before washing hands, swimming, exercising, cleaning, or applying personal body products. Avoiding contact with soaps, perfumes, lotions, makeup, and hair products will also help maintain the jewelry’s shine. Using rubber or metal safety backs on earrings is crucial to prevent loss.
Sources
Conclusion
Opal and tourmaline, the captivating birthstones of October, offer a rich tapestry of history, lore, and gemological intrigue. From the ancient beliefs surrounding opal’s mystical properties to the vibrant colors of tourmaline inspiring artistic expression, these gems continue to enchant and inspire. Understanding their origins, properties, and care requirements allows enthusiasts and jewelry lovers to fully appreciate the beauty and significance of these dazzling October birthstones.