October is uniquely blessed with not one, but two recognized birthstones: tourmaline and opal. Both gemstones boast a rich history, captivating beauty, and distinct symbolic meanings, making them cherished choices for those born in the tenth month of the year. While opal historically held prominence as the sole October birthstone, tourmaline was added to the list in the early 20th century, offering a wider spectrum of color and choice for those seeking a meaningful gemstone connection. This article will delve into the geological origins, historical significance, gemological properties, and cultural lore surrounding both tourmaline and opal, providing a comprehensive overview of these fascinating gems.
A History of Shared Recognition
The tradition of associating specific gemstones with months of the year dates back centuries, evolving alongside cultural beliefs and the availability of gemstones. The assignment of birthstones was initially linked to the twelve tribes of Israel and their corresponding stones on the Breastplate of Aaron, as described in the Book of Exodus. Over time, this tradition adapted, with different cultures and gem merchants influencing the modern birthstone list.
The inclusion of multiple birthstones for certain months, such as October, reflects a desire to accommodate evolving traditions and address fluctuations in gemstone availability. As naturally occurring crystal resources became depleted with increased use in jewelry, assigning multiple gemstones to a single month provided greater accessibility and flexibility for consumers. Both opal and tourmaline have enjoyed a long history of appreciation, though their recognition as official October birthstones developed at different times. Opal’s association with the month is ancient, while tourmaline’s formal designation is more recent.
The Allure of Opal: A Play of Color
Opal, derived from the Latin opalus and potentially linked to the Sanskrit upala meaning “precious stone,” is celebrated for its remarkable “play-of-color”—a shifting display of iridescent hues. This phenomenon, described by writers as resembling fireworks, galaxies, and volcanoes, is what sets opal apart from many other gemstones. The play-of-color is caused by the diffraction of light passing through microscopic silica spheres within the stone.
Historically, opal’s origins are traced to India, where it was known as Upala and imported into the West. Ancient Greeks believed opal possessed the power to prophesy and protect against disease, while in Europe, it became associated with purity, hope, and truth. Bedouins attributed the stone’s vibrant colors to captured lightning, believing it fell from the sky during thunderstorms. Opal was considered to embody the virtues and powers of all colored stones. It is also traditionally given as a gift for the 14th wedding anniversary.
Opal is a mineraloid, formed by the gradual heating of silica gel found in cracks within rocks. While once considered relatively rare, the discovery of rich mines in Australia significantly increased its availability. Despite this, the unique interplay of colors within each opal continues to make it a prized and cherished gemstone. Opal comes in two main varieties: precious opal, which exhibits play-of-color, and common opal, which does not.
Tourmaline: A Spectrum of Hues
The name “tourmaline” originates from the Sinhalese word toramalli, meaning “stone with mixed colors.” This aptly describes the gemstone’s most defining characteristic: its extraordinary range of colors. Unlike many gemstones that are typically associated with a single hue, tourmaline occurs in a vast spectrum, including pink, red (rubellite), emerald-green (chrome tourmaline), and the vibrant blues and greens of paraíba tourmaline. In fact, some tourmaline crystals even display multiple colors within a single stone, known as “watermelon tourmaline.”
For centuries, tourmaline was often misidentified as 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). Similarly, green tourmaline crystals discovered in Brazil during the 1500s were initially mistaken for emeralds. It wasn’t until the 19th century that tourmaline was formally recognized as a distinct mineral species.
Tourmaline’s history is also marked by the fascination of Empress Dowager Tzu-Hsi of China, who acquired nearly the entire production from a California mine in the late 1800s. She was so enamored with the gemstone that she was buried with a pink tourmaline pillow, and the remainder of her collection was crafted into exquisite carvings.
Gemological Properties: A Comparative Overview
Both tourmaline and opal possess unique gemological properties that contribute to their distinct appeal.
Tourmaline typically forms in distinctive prism-like crystals with long hexagonal structures. It primarily consists of the mineral elbaite. Its Mohs hardness ranges from 7 to 7.5, making it relatively durable and suitable for everyday wear.
Opal, on the other hand, is less durable, with a Mohs hardness of 5 to 6.5. This makes it more susceptible to scratches and damage compared to tourmaline.
The following table summarizes key gemological properties:
| Property | Tourmaline | Opal |
|---|---|---|
| Chemical Formula | Complex borosilicate | Hydrated silica |
| Mohs Hardness | 7 - 7.5 | 5 - 6.5 |
| Crystal System | Trigonal | Amorphous |
| Specific Gravity | 3.06 - 3.10 | 1.98 - 2.15 |
| Notable Feature | Wide range of colors | Play-of-color |
Symbolism and Metaphysical Beliefs
Both tourmaline and opal are imbued with symbolic meanings and metaphysical beliefs. Tourmaline, with its diverse colors, is associated with a range of properties. Black tourmaline is believed to offer protection from negativity and enhance self-confidence, while pink tourmaline embodies love, compassion, and gentleness. Green tourmaline is thought to promote courage, strength, and stamina. Tourmaline is also the traditional gemstone for celebrating an eighth wedding anniversary.
Opal, historically, has been linked to hope, purity, and truth. It is believed to inspire confidence and bring positive energy to the wearer. The stone’s vibrant colors are often associated with autumn, making it a particularly fitting birthstone for October.
Care and Cleaning
Due to their differing hardness levels, tourmaline and opal require different care approaches. Tourmaline’s greater durability makes it suitable for everyday wear, but it should still be protected from harsh impacts and extreme temperature changes. Cleaning tourmaline can be done with warm, soapy water and a soft brush.
Opal, being more delicate, requires more careful handling. It should be protected from scratches and impacts, and exposure to harsh chemicals should be avoided. Cleaning opal is best done with a soft cloth and lukewarm water. Avoid ultrasonic cleaners and steam cleaners, as these can damage the stone.
Conclusion
Tourmaline and opal, the dual birthstones of October, represent a captivating blend of history, beauty, and symbolism. From the ancient origins of opal in India to the centuries of misidentification surrounding tourmaline, both gemstones have a rich and fascinating story to tell. Their unique gemological properties, coupled with their diverse colors and metaphysical beliefs, make them cherished choices for jewelry and meaningful gifts. Whether one prefers the iridescent play-of-color of opal or the vibrant spectrum of tourmaline, these October birthstones offer a connection to the earth’s beauty and the enduring power of gemstones.