For those born on October 17th, a unique pairing of gemstones marks their birthstone—opal and tourmaline. These two gems, celebrated for their vibrant colors and rich histories, offer a fascinating duality in the world of birthstones. Revered for their aesthetic beauty and symbolic resonance, opal and tourmaline have been cherished for centuries. This article explores the geological origins, historical significance, gemological properties, and cultural meanings of these stones, providing a comprehensive overview for enthusiasts, buyers, and students of gemology.
History and Lore
The story of October’s birthstones is one of evolving tradition. Originally, opal held sole claim to the month, its name originating from the Sanskrit word upala, meaning “precious stone,” and later adopted into the Greek opallios, signifying “to see a change of color.” Ancient civilizations attributed various powers to opal. Ancient Greeks believed it bestowed the gift of prophecy and protection from disease, while Bedouins considered it to be solidified lightning fallen from the sky during thunderstorms. Europeans long regarded opal as a symbol of purity, hope, and truth, believing it embodied the virtues of all colored stones.
However, in 1912, the National Association of Jewelers officially added pink tourmaline as a secondary birthstone for October. This shift was likely due to the increasing popularity of tourmaline and its diverse color range. The Egyptians believed tourmaline’s multitude of colors stemmed from its journey down a rainbow from the sun to earth. Chinese Empress Dowager Tzu-Hsi’s profound affection for pink tourmaline in the late 1800s further cemented its status; she acquired nearly the entire production from a California mine and was even buried with pink tourmaline, alongside carvings made from her extensive collection.
Opal also holds a specific association with anniversaries, traditionally gifted to celebrate the 14th wedding anniversary.
Geological Formation and Sources
Opal is unique in its formation, being a hydrated silica gel. Over millennia, it can even replace parts of animal skeletons, plants, or wood, creating what are known as opalized fossils or opalized wood. The sources for opal are not explicitly detailed in the provided materials beyond a general mention of India as the original source for opals brought to the Western world.
Tourmaline, on the other hand, is a complex borosilicate mineral. It forms in distinctive prism-like crystals with long hexagonal structures. The sources for tourmaline are also not extensively detailed, though the materials mention a California mine that supplied Empress Dowager Tzu-Hsi with pink tourmaline. The name “tourmaline” itself comes from the Sinhalese word turmali, meaning “mixed colored stones,” reflecting the gem’s incredible color diversity. Some tourmaline crystals even exhibit multiple colors within a single stone, known as watermelon tourmaline.
Gemological Properties
Both opal and tourmaline possess distinct gemological properties. Opal’s defining characteristic is its “play-of-color,” a shifting display of rainbow hues caused by its internal structure diffracting light. It registers between 5.5 and 6.5 on the Mohs hardness scale. Tourmaline, with a hardness of 7 to 7.5 on the Mohs scale, is a more durable gemstone.
Tourmaline is particularly notable for its wide range of colors, occurring in virtually all hues. Pink tourmaline, the specific variety associated with October 17th, showcases a striking pink hue with variations throughout the color spectrum. Tourmaline’s chemical composition is primarily elbaite, a mineral that contributes to its crystal structure and beauty when exposed to light.
Here's a table summarizing the key gemological properties:
| Property | Opal | Tourmaline |
|---|---|---|
| Mineral | Hydrated Silica | Complex Borosilicate |
| Color | Multicolored | Virtually all colors |
| Hardness (Mohs) | 5.5-6.5 | 7-7.5 |
| Play-of-Color | Present | Absent |
Symbolism and Metaphysical Beliefs
Opal has long been associated with hope, purity, and truth. It is considered a stone of imagination and creativity. Pink tourmaline, as a more recent addition to the October birthstone family, symbolizes friendship, compassion, and balance. It is considered a heart-centered stone, promoting emotional well-being. Some believe rose quartz, another alternative October birthstone, is a powerful stone for love, encouraging self-love and forgiveness.
The materials also touch upon superstitions surrounding opal, though these are not universally accepted within formal gemology.
Care and Cleaning
Due to its lower hardness, opal requires careful handling. It is more susceptible to scratches and damage than tourmaline. Tourmaline, being harder, is more durable and can withstand more wear and tear. Specific cleaning instructions are not detailed in the provided sources, but general gemstone care guidelines would apply: cleaning with warm, soapy water and a soft cloth is recommended for both stones. Avoid harsh chemicals and ultrasonic cleaners, especially for opal.
October Birthstone and Zodiac Associations
The provided sources link opal, peridot, and lapis lazuli to the zodiac sign Libra (September 23 - October 22), emphasizing qualities like sociability and fairness. Aquamarine, coral, and topaz are associated with Scorpio (October 24 - November 22). Opal is also connected to Friday, with rose quartz and topaz also being gemstones for that day. Tourmaline is specifically linked to 6 am.
Conclusion
Opal and tourmaline, the dual birthstones of October 17th, represent a captivating blend of history, beauty, and symbolism. Opal, with its ancient roots and mesmerizing play-of-color, embodies hope and purity. Tourmaline, a more recent addition, offers a spectrum of colors and symbolizes friendship and compassion. Both gemstones provide a meaningful connection to the month of October, offering wearers a unique and beautiful expression of their birthdate. Their enduring appeal lies not only in their aesthetic qualities but also in the rich cultural lore and metaphysical beliefs that have surrounded them for centuries.