October is unique among the calendar months, boasting not one, but two recognized birthstones: opal and pink tourmaline. Both gemstones offer a stunning array of colors and captivating beauty, providing those born in October with a choice that reflects their individual preferences. While opal holds the distinction as the traditional October birthstone, pink tourmaline gained recognition as a modern alternative in 1912, expanding the options for celebrating October birthdays. This article will delve into the history, geological origins, gemological properties, and symbolism of both opal and pink tourmaline, offering a comprehensive overview of these fascinating gemstones.
A History of Significance
The story of opal stretches back to ancient times. Its name is believed to originate from the Sanskrit word upala, meaning “precious stone,” which was adopted into the Roman opalus. Ancient Greeks associated opal with the gift of prophecy and protection from disease, while Bedouins believed the stone contained lightning and fell to earth during thunderstorms. Throughout history, Europeans considered opal a symbol of purity, hope, and truth, even believing it embodied the virtues of all colored stones.
Pink tourmaline, while appreciated for centuries, gained prominence more recently. In the late 19th century, the Empress Dowager Tzu-Hsi of China developed a particular fondness for pink tourmaline, acquiring nearly the entire production from California mines. She even requested to be buried with a pillow of the gemstone, and the remainder of her collection was crafted into intricate carvings.
The shift to recognize tourmaline as an October birthstone occurred in 1912 when the National Association of Jewelers sought to provide alternatives for months with either rare or misunderstood classic birthstones. Tourmaline, with its diverse color palette, proved a fitting addition, ultimately sharing the spotlight with opal.
Geological Formation and Sources
Opal is not a true crystal but a mineraloid – a substance with a crystalline structure but lacking a defined crystal lattice. It is formed by the gradual natural heating of silica gel found in cracks and voids within rocks. The resulting structure contains microscopic spheres of silica that diffract light, creating the characteristic “play-of-color.” While opal has been sourced from various locations, Australia is currently the most significant producer.
Pink tourmaline, conversely, is a crystalline mineral, specifically a variety of the elbaite group of tourmalines. These gemstones form in distinctive prism-like crystals with long hexagonal structures. The color pink arises from the presence of manganese within the crystal structure. While pink tourmaline can be found in several locations, a notable historical source was California, particularly due to the demand from Empress Tzu-Hsi.
Within the opal family, variations exist based on background color and the presence of play-of-color. Fire opal, predominantly sourced from Mexico, displays vibrant red, orange, or yellow backgrounds and may or may not exhibit play-of-color. Crystal opal is known for its transparency and superior play-of-color, while water opal presents a more subtle appearance.
Gemological Properties
Both opal and pink tourmaline possess distinct gemological properties that contribute to their unique appeal.
Opal:
- Composition: Hydrated amorphous silica (SiO₂·nH₂O)
- Play-of-Color: The defining characteristic, caused by the diffraction of light.
- Hardness (Mohs Scale): 5.5 – 6.5
- Specific Gravity: 1.98 – 2.15
- Transparency: Ranges from transparent to opaque.
Pink Tourmaline:
- Composition: Complex borosilicate (typically elbaite)
- Color: Shades of pink, ranging from delicate blush to vibrant magenta.
- Hardness (Mohs Scale): 7 – 7.5
- Specific Gravity: 3.07 – 3.10
- Transparency: Typically transparent to translucent.
The difference in hardness is significant. Opal, being softer, requires more careful handling to avoid scratches and damage. Tourmaline’s greater hardness makes it more durable for everyday wear.
Symbolism and Metaphysical Beliefs
Throughout history, both opal and pink tourmaline have been imbued with symbolic meanings. Opal has long been associated with hope, purity, and truth. It was believed to bestow prophetic gifts and offer protection from illness. Some modern interpretations suggest opal encourages emotional expression and creativity.
Pink tourmaline is often linked to love, compassion, and emotional healing. It is considered a heart-centered stone that promotes friendship and balance. Rose quartz, another alternative October birthstone, is also strongly associated with love and self-forgiveness. Some believe pink tourmaline can help to release emotional pain and foster a sense of inner peace.
Care and Cleaning
Due to their differing hardness levels, opal and pink tourmaline require different care approaches. Opal is relatively soft and susceptible to scratches. It should be stored separately from harder gemstones and cleaned with a soft cloth and mild soapy water. Avoid ultrasonic cleaners and harsh chemicals, as these can damage the stone.
Pink tourmaline, being more durable, can withstand more rigorous cleaning. It can be cleaned with warm soapy water, a soft brush, and rinsed thoroughly. Ultrasonic cleaners are generally safe for pink tourmaline, but caution should be exercised with stones that may have inclusions.
Varieties and Value Factors
Opal is categorized into several varieties, each with its own value factors. Fire opal, with its vibrant body color, is valued for the evenness and intensity of its hue. Crystal opal, known for its transparency and play-of-color, is often highly prized. Water opal, with its subtle appearance, is generally more affordable. The intensity, pattern, and range of colors within the play-of-color significantly impact an opal’s value.
Pink tourmaline’s value is influenced by color, clarity, cut, and carat weight. Vivid, saturated pink hues are generally more desirable. The presence of inclusions can affect clarity, and well-cut stones that maximize brilliance are preferred. Watermelon tourmaline, displaying multiple colors within a single crystal, is a particularly sought-after variety.
Conclusion
October’s birthstones, opal and pink tourmaline, represent a captivating duality. Opal, with its ancient history and mesmerizing play-of-color, embodies hope and inspiration. Pink tourmaline, a more recent addition to the birthstone family, symbolizes love, compassion, and emotional healing. Both gemstones offer a unique and beautiful way to celebrate those born in the tenth month, providing a spectrum of choices to suit individual tastes and preferences. Their distinct geological origins, gemological properties, and symbolic meanings contribute to their enduring appeal, making them treasured gemstones for generations to come.