October boasts not one, but two recognized birthstones: opal and tourmaline. Both gemstones offer a stunning array of colors and possess unique histories, making them significant choices for those born in the tenth month. This article will delve into the origins, properties, symbolism, and historical context of these captivating gems, drawing solely from available sources.
History and Lore
The story of opal, the traditional October birthstone, traces back to ancient India, where it was known as upala, meaning “precious stone” in Sanskrit. This name evolved into opalus in ancient Rome. Throughout history, opal has been imbued with diverse meanings. Ancient Greeks believed it bestowed the gift of prophecy and offered protection from disease. Europeans long associated the gem with purity, hope, and truth, even believing it embodied the virtues of all colored stones. Bedouin tribes held the belief that opal contained lightning and originated from the sky during thunderstorms. Opal is also traditionally given to celebrate the 14th wedding anniversary.
Tourmaline’s history is somewhat more complex, stemming from centuries of misidentification. The name “tourmaline” originates from the Sinhalese word tourmali, meaning “mixed stones,” reflecting the gem’s wide range of colors. Historically, red tourmaline was often mistaken for ruby, blue tourmaline for sapphire, and green tourmaline for peridot or spinel, particularly in locations like Sri Lanka and Burma. It wasn’t until the 19th century, with the development of modern gemological testing techniques, that tourmaline was recognized as a distinct mineral species. In 1912, the National Association of Jewelers designated pink tourmaline as an alternative to opal for October, a decision later accepted by the American Gem Society and the National Retail Jewelers Council. Today, tourmaline of any color is widely accepted as an October birthstone.
Geological Formation and Sources
Opal is renowned for its “play-of-color,” a phenomenon caused by the diffraction of light within its internal structure. While found in various locations, Australia is the primary source of opal globally.
Tourmaline’s formation occurs in a variety of geological environments, contributing to its diverse color range. Brazil and the United States are significant sources, but tourmaline is also found in Sri Lanka, Burma, and other locations. The most prized variety, Paraíba tourmaline, a copper-bearing gem exhibiting intense violet-blue and blue-green hues, originates from Brazil. Green tourmaline crystals were first discovered by Spanish conquistadors in Brazil during the 1500s, though initially mistaken for emeralds.
Gemological Properties
Both opal and tourmaline exhibit a wide range of properties, though they differ significantly in their composition and characteristics.
Opal: Sources do not provide specific chemical formulas or refractive indices for opal. Its defining characteristic is its play-of-color, a visual effect resulting from the diffraction of light.
Tourmaline: Tourmaline’s chemical composition is complex, with a general formula of XY3Z6(BO3)3Si6O18(OH,F)4. This allows for a vast spectrum of colors, unmatched by many other gemstones. Popular varieties include pink (rubellite), red (rubellite), emerald green, and the highly sought-after Paraíba tourmaline. Some tourmaline exhibits piezoelectricity, meaning it generates an electrical charge when pressure is applied – a property utilized in pressure gauges for submarines.
The following table summarizes the color variations of tourmaline:
| Tourmaline Color | Description |
|---|---|
| Pink/Red (Rubellite) | Traditional choice for October birthdays |
| Green | Often mistaken for emerald in the past |
| Blue/Green (Paraíba) | Rarest and most prized variety |
| Watermelon | Displays both pink and green hues |
Symbolism and Metaphysical Beliefs
Opal has long been associated with hope, purity, and truth. It is believed to inspire creativity and symbolize fidelity.
Tourmaline’s symbolism varies depending on its color. Pink tourmaline embodies love and compassion, while black tourmaline is thought to protect against negativity and enhance self-confidence. Green tourmaline is believed to promote courage, strength, and stamina. Ancient mystics believed tourmaline could inspire artistic expression. The last empress of the Chi’ing Dynasty in China was a passionate collector of tourmaline, particularly vivid pink and magenta shades, and was even buried with a tourmaline pillow.
Care and Cleaning
Sources provide limited information regarding the specific care requirements for opal and tourmaline. However, both gemstones require gentle handling and cleaning to preserve their beauty. Protective storage is recommended to avoid damage. Further detailed care instructions would require information beyond the provided sources.
Conclusion
Opal and tourmaline, the captivating birthstones of October, offer a rich tapestry of history, lore, and gemological intrigue. Opal, with its ancient origins and mesmerizing play-of-color, embodies hope and creativity. Tourmaline, a relatively recent addition to the October birthstone family, showcases an unparalleled range of colors and is believed to promote various positive attributes depending on its hue. Both gemstones continue to enchant and inspire, making them cherished symbols of the tenth month.