October is unique among the calendar months in possessing two recognized birthstones: the captivating opal and the vibrant tourmaline. Both gemstones offer a stunning array of colors and optical phenomena, making them cherished adornments and objects of fascination for centuries. While opal holds the distinction as the traditional October birthstone, tourmaline has gained prominence as a modern alternative, offering wearers a choice reflecting personal preference and symbolic resonance. This article will delve into the history, geological origins, gemological properties, and cultural significance of both opal and tourmaline, exploring their enduring appeal as symbols of October.
History and Lore
The story of October’s birthstones is one of evolving tradition. Early formalized lists of birthstones, beginning in the 19th century, initially designated opal as the sole stone for October. The Tiffany & Co. pamphlet of 1870 highlighted opal, and the National Association of Jewellers in 1912 solidified this designation, while simultaneously introducing tourmaline as an alternative. This dual recognition reflects the growing appreciation for the diverse beauty and symbolism offered by both gems.
Opal’s history stretches back to antiquity. Its name is believed to originate from the Sanskrit word upala, meaning “precious stone,” which was adopted into the Roman opalus. Ancient civilizations attributed various powers to opal. Bedouins believed the stone held lightning and fell from the sky during thunderstorms, while ancient Greeks associated it with prophecy and protection from disease. Europeans long considered opal a symbol of purity, hope, and truth, believing it embodied the virtues of all colored stones.
Despite its positive associations throughout much of history, opal experienced a period of superstition in the 19th century. A popular novel published in 1829, which featured an opal bringing misfortune to its wearer, contributed to a widespread belief that opals were cursed, particularly for those not born in October. This stigma temporarily diminished opal’s popularity, but its inherent beauty ultimately prevailed.
Tourmaline’s history, while less steeped in ancient lore than opal’s, is nonetheless rich. The Egyptians believed tourmaline came in so many colors because it traveled down a rainbow from the sun to earth. In more recent times, pink tourmaline gained prominence as an alternative October birthstone in 1912, symbolizing friendship, compassion, and balance.
Geological Formation and Sources
Opal is not a true crystal but a mineraloid – a naturally occurring amorphous substance. It is formed by the gradual natural heating of silica gel found in the cracks and voids of rocks. The resulting structure contains microscopic spheres of silica that diffract light, creating the characteristic “play-of-color” that makes opal so prized.
Australia is by far the most productive source of opal in the world, yielding the vast majority of precious opal available today. However, significant deposits are also found in Ethiopia, Mexico, and Brazil, as well as in Central Europe, Honduras, Indonesia, Madagascar, Peru, Turkey, and the United States.
Tourmaline, in contrast, is a crystalline borosilicate mineral. It forms in igneous and metamorphic rocks and is known for its exceptional range of colors, caused by trace elements within its chemical composition. Tourmaline is found in various locations worldwide, though specific sources are not detailed in the provided materials.
Gemological Properties
Both opal and tourmaline exhibit unique gemological properties that contribute to their beauty and desirability.
Opal: The most defining characteristic of opal is its play-of-color – the shifting display of rainbow hues when the stone is viewed from different angles or under varying light conditions. This phenomenon is caused by the diffraction of light within the microscopic silica spheres. Opal’s hardness ranges from 5.5 to 6.5 on the Mohs scale, making it relatively delicate and susceptible to scratching. It typically has a specific gravity between 1.98 and 2.20.
Tourmaline: Tourmaline is a more durable gemstone, with a hardness ranging from 7 to 7.5 on the Mohs scale. This makes it suitable for everyday wear. It exhibits a wide range of colors, including pink, green, blue, and multicolored varieties. The chemical composition of tourmaline is complex, varying depending on the specific trace elements present.
The following table summarizes key gemological properties:
| Property | Opal | Tourmaline |
|---|---|---|
| Hardness (Mohs) | 5.5 - 6.5 | 7 - 7.5 |
| Composition | Hydrated Silica | Borosilicate |
| Play-of-Color | Present | Absent |
| Specific Gravity | 1.98 - 2.20 | Varies |
Symbolism and Metaphysical Beliefs
Throughout history, both opal and tourmaline have been imbued with symbolic meanings and metaphysical properties.
Opal is traditionally associated with purity, hope, and perspective. Ancient Romans referred to opals as cupid paederos, or “child as beautiful as love.” Many believe opal possesses healing powers, particularly related to vision and the mind, with claims that it can treat eyesight problems, boost cognitive abilities, and even grant glimpses into the future. Despite past superstitions, opal is now widely regarded as a stone of good luck and positive energy.
Tourmaline, particularly pink tourmaline, symbolizes compassion, open-mindedness, and forgiveness, earning it the nickname “Stone of Reconciliation.” It is believed to boost energy, encourage love, and help smooth relationship troubles. Some believe tourmaline offers protection and promotes emotional balance.
Care and Cleaning
Due to its relatively lower hardness, opal requires careful handling and cleaning. It is susceptible to scratching and should be protected from harsh impacts. Cleaning opal jewelry can be done with a soft cloth and mild soapy water. Avoid ultrasonic cleaners and harsh chemicals.
Tourmaline, being more durable, is easier to care for. It can be cleaned with warm soapy water and a soft brush. Ultrasonic cleaners are generally safe for tourmaline, but it’s always best to exercise caution.
Conclusion
Opal and tourmaline, the dual birthstones of October, represent a captivating blend of history, beauty, and symbolism. Opal, with its mesmerizing play-of-color and ancient lore, embodies hope and perspective. Tourmaline, with its vibrant hues and association with compassion and balance, offers a modern alternative. Both gemstones continue to enchant and inspire, making them cherished symbols of October and treasured additions to any jewelry collection.