October boasts not one, but two recognized birthstones: tourmaline and opal. Both gemstones are celebrated for their captivating beauty and rich histories, offering a diverse range of options for those born in the tenth month of the year. While opal holds the distinction of being the traditional October birthstone, tourmaline was added as a modern alternative in 1912, expanding the choices and symbolic meanings associated with this autumn birth month. This article will delve into the history, geological origins, gemological properties, and symbolism of both tourmaline and opal, providing a comprehensive overview of these vibrant gemstones.
A History of Significance
Opal’s history stretches back to ancient times, with origins traced to India, where it was known as “Upala,” meaning “precious stone.” The Romans referred to it as “opalus,” and the name itself is believed to derive from the Greek word “Opallos,” signifying a shift in color. Throughout history, opal has been revered for its unique play-of-color, inspiring tales of its celestial origins. Bedouins believed opals contained lightning and fell from the sky during thunderstorms, while the ancient Greeks associated the stone with the power of prophecy and protection from disease. In Europe, opal was long considered a symbol of purity, hope, and truth, embodying a multitude of virtues within a single gem.
Tourmaline’s story is somewhat more recent in terms of formal recognition, though its presence has been appreciated for centuries. The Sinhalese people of Sri Lanka named the gem “turamali,” meaning “stone with mixed colors,” a fitting description given its extraordinary range of hues. For a long period, tourmaline was often mistaken for other gemstones due to its diverse coloration. A notable example is the “Caesar’s Ruby” in the Russian crown jewels, which is, in fact, a red tourmaline (rubellite). Green tourmaline crystals discovered in Brazil during the 1500s were initially believed to be emeralds. It wasn’t until the 19th century that tourmaline was definitively recognized as a distinct mineral species. In the late 1800s, the Empress Dowager Tzu-Hsi of China developed a strong fondness for pink tourmaline, acquiring nearly all the production from California mines and even being buried with a pillow of the gem.
Geological Formation and Sources
Opal’s formation is unique, often occurring in sedimentary environments where silica-rich water seeps into cracks and voids in the earth. Over time, this water evaporates, leaving behind deposits of hydrated silica – the key component of opal. Significant opal mining occurs in Australia, which is the primary source of this gemstone. Ethiopia is also a notable producer, contributing to the diversity of opal character.
Tourmaline, on the other hand, forms in igneous and metamorphic rocks, often within pegmatites – coarse-grained igneous rocks. The gem’s diverse colors are attributed to the presence of various elements within its crystal structure, primarily elbaite. Tourmaline is sourced from a variety of locations worldwide, including Brazil, the United States, and Sri Lanka, the origin of its name. The variety known as Paraiba tourmaline, prized for its neon blue or green color, is primarily found in Brazil.
Gemological Properties
Tourmaline boasts a Mohs hardness of 7 to 7.5, making it a relatively durable gemstone suitable for everyday wear. Its chemical composition is complex, varying depending on the specific type of tourmaline, but it is a borosilicate mineral. The gem exhibits a wide range of colors, including pink, green, blue, purple, and even multi-colored varieties like watermelon tourmaline.
Opal, with a Mohs hardness of 5-6.5, is a softer gemstone than tourmaline and requires more careful handling. It is a hydrated amorphous form of silica, meaning it lacks a defined crystal structure. The defining characteristic of opal is its “play-of-color,” a mesmerizing display of iridescent hues caused by the diffraction of light within its internal structure. Opal’s colors range from milky whites and deep blacks to flashes of yellow, orange, green, red, and blue.
The following table summarizes the key gemological properties:
| Property | Tourmaline | Opal |
|---|---|---|
| Mohs Hardness | 7 - 7.5 | 5 - 6.5 |
| Chemical Formula | Complex Borosilicate | Hydrated Silica |
| Crystal System | Trigonal | Amorphous |
| Luster | Vitreous | Vitreous/Resinous |
| Play-of-Color | No | Yes |
Symbolism and Metaphysical Beliefs
Both tourmaline and opal are imbued with symbolic meanings and metaphysical properties. Tourmaline, with its diverse colors, is believed to represent love, prosperity, and harmony. Different colors are associated with specific benefits: pink tourmaline embodies love and compassion, black tourmaline offers protection from negativity and enhances self-confidence, and green tourmaline promotes courage, strength, and stamina. Ancient mystics believed tourmaline could inspire artistic expression.
Opal, historically, has been associated with hope, purity, and truth. It is considered a stone of inspiration, creativity, and emotional healing. The Bedouins believed it contained lightning, while the ancient Greeks linked it to prophecy and protection. Opal is also traditionally given as a gift for the 14th wedding anniversary.
Care and Cleaning
Due to its greater hardness, tourmaline is more resistant to scratches and abrasions than opal, making it suitable for everyday wear. Cleaning tourmaline is relatively straightforward: warm soapy water and a soft brush are generally sufficient.
Opal, being softer, requires more delicate care. Avoid harsh chemicals, ultrasonic cleaners, and steam cleaners, as these can damage the stone. Clean opal with a soft cloth and lukewarm water. It is also advisable to store opal jewelry separately from other gemstones to prevent scratches.
The Popularity of October Birthstones
According to data from Google Trends, opal currently enjoys a higher search volume than tourmaline, indicating greater public interest. However, both gemstones hold significant appeal for those seeking a unique and meaningful birthstone. The choice between opal and tourmaline ultimately comes down to personal preference, considering factors such as color preference, durability requirements, and symbolic resonance.
Conclusion
Tourmaline and opal, the dual birthstones of October, represent a captivating blend of history, beauty, and symbolism. Opal, with its iridescent play-of-color, has been cherished for millennia, while tourmaline, with its remarkable range of hues, has gained prominence as a modern alternative. Both gemstones offer a unique and meaningful connection to the tenth month of the year, making them ideal gifts for October birthdays and treasured additions to any gemstone collection. Their distinct geological origins and gemological properties further enhance their allure, solidifying their place as beloved and significant gemstones.