Opal, celebrated as one of the primary birthstones for October alongside tourmaline, is a gemstone steeped in history, lore, and captivating beauty. Renowned for its unique “play-of-color,” opal has fascinated cultures for centuries, symbolizing hope, purity, and truth. This article delves into the origins, geological formation, gemological properties, historical significance, and modern appreciation of this remarkable gemstone.
History and Lore
The story of opal’s name is itself a journey through time and language. Its origins are believed to trace back to India, where the Sanskrit term upala, meaning “precious stone,” was used to describe the gem. This evolved into opalus in ancient Rome. Throughout history, opal has been imbued with diverse meanings and beliefs. Ancient Greeks associated the stone with the gift of prophecy and protection from disease, while Bedouins believed opals contained lightning and descended from the sky during thunderstorms. Europeans historically viewed opal as a symbol of purity, hope, and truth, and for centuries, it was thought to embody the virtues of all other colored stones.
The October birthstone has long been associated with positive attributes. It is believed to bring confidence and hope to the wearer, making it a particularly meaningful gift for those born in October. The stone’s ability to display a spectrum of colors has inspired comparisons to natural phenomena like fireworks, galaxies, and volcanoes, further enhancing its mystique. Opal is also traditionally given to commemorate the 14th wedding anniversary.
Geological Formation and Sources
Opal is unique in that it is not a crystalline gemstone like diamonds or rubies, but rather a mineraloid – an amorphous form of hydrated silica. It forms through the gradual natural heating of silica gel found within cracks and voids in rocks. The resulting structure contains microscopic spheres of silica, and the size and arrangement of these spheres determine the type of play-of-color exhibited.
While opals were initially sourced from India, the discovery of rich mines in Australia dramatically increased their availability. Australia remains the world’s primary source of opal today. The sources do not specify other locations, so information regarding other mining locations is unavailable.
Gemological Properties
Opal is characterized by its distinctive play-of-color, a visual phenomenon caused by the diffraction of light as it passes through the microscopic silica spheres within the stone. This creates flashes of rainbow hues that shift and change with the viewing angle. Opals are categorized into two main varieties: precious and common. Precious opals exhibit this play-of-color, while common opals do not.
The sources do not provide specific details regarding the chemical formula, refractive index, or hardness of opal. However, commercially available opal rings often feature stones around 2mm in size, set in bands approximately 1mm thick. These rings are typically crafted from 925 sterling silver, with finish options including 18K gold, sterling silver, and rose gold.
Symbolism and Metaphysical Beliefs
Beyond its aesthetic appeal, opal is believed to possess various healing properties and metaphysical attributes. Pink opal, in particular, is thought to offer respite from ailments affecting the eyes, spleen, throat, pancreas, and bone marrow. Wearing opal is also believed to instill a sense of peace and foster loving, devoted relationships within the family.
Tourmalines, the other birthstone for October, are also believed to have healing properties, balancing hormones and potentially aiding in the fight against genetic disorders. They are thought to calm the nerves and enhance creativity. While the sources focus primarily on opal, the inclusion of tourmaline as an October birthstone adds another layer of meaning and potential benefit for those born in this month.
Opal in Jewelry
Opal is a versatile gemstone used in a wide range of jewelry designs. It is frequently featured in rings, earrings, pendants, and bracelets. Opal rings, such as the duo birthstone rings featuring a combination of opal and a chosen birthstone, are popular choices for personalized jewelry. These rings are often set in sterling silver with gold finishes.
The sources showcase a variety of opal jewelry styles, including baguette stack bands, halo pendants, bezel-set earrings, and full eternity bands. Opal gemstones come in various cuts, including oval, pear, marquise, and round. The price of opal jewelry varies significantly, ranging from approximately $162 to over $1800, depending on the size, quality, and setting of the stone.
Caring for Opal Jewelry
While beautiful, opal requires careful handling due to its relative softness and susceptibility to damage. The sources do not provide specific care instructions, but based on its composition, it is advisable to avoid harsh chemicals, extreme temperatures, and abrasive materials. Gentle cleaning with a soft cloth and mild soapy water is recommended. It is also important to store opal jewelry separately from other gemstones to prevent scratching.
Purchasing Opal Jewelry
When selecting opal jewelry, it is important to consider the quality of the play-of-color, the body tone of the stone, and the overall craftsmanship of the piece. Look for opals with vibrant, distinct colors that shift and change as the stone is moved. The body tone refers to the background color of the opal, which can range from white to black. Black opals, with their dark body tone, are generally considered the most valuable.
The size of the opal is also a factor to consider. The sources mention opal gemstones ranging from 5mm to 7mm in diameter, but larger stones are available. Finally, pay attention to the setting and the quality of the metal used in the jewelry. Sterling silver with gold finishes is a common choice, but other metals like gold and platinum are also used.
Conclusion
Opal, the captivating October birthstone, continues to enchant with its shifting colors, rich history, and enduring symbolism. From its ancient origins in India to its modern-day appreciation as a prized gemstone, opal has captured the imagination of cultures across the globe. Whether admired for its beauty, cherished for its metaphysical properties, or gifted as a symbol of hope and confidence, opal remains a truly remarkable and treasured gemstone.