October boasts not one, but two recognized birthstones: pink tourmaline and opal. Both gemstones offer a stunning array of colors and a rich history, making them cherished choices for those born in the tenth month. While pink tourmaline has gained prominence as the modern October birthstone, opal holds a long-standing tradition and continues to captivate with its unique play-of-color. This article will explore the geological origins, historical significance, gemological properties, and symbolism of both these vibrant gemstones.
History and Lore
The history of opal stretches back to ancient times. Its name is believed to have originated in India, where it was known as upala, meaning “precious stone,” in Sanskrit. This term evolved into opalus in ancient Rome. Ancient Greeks associated opal with the gift of prophecy and protection from disease, while Europeans once considered it a symbol of purity, hope, and truth, believing it embodied the virtues of all colored stones. Bedouins held the belief that opal contained lightning and fell from the sky during thunderstorms.
Pink tourmaline’s history, while not as ancient as opal’s, is nonetheless fascinating. In the late 19th century, the Chinese Empress Dowager Tzu-Hsi developed a strong fondness for pink tourmaline, purchasing nearly the entire production from California mines. Her devotion continued after her death, as she was buried with a pink tourmaline pillow, and the remainder of her collection was crafted into intricate carvings.
Geological Formation and Sources
Tourmaline, including the pink variety, forms in distinctive prism-like crystals with long hexagonal structures. These crystals exhibit remarkable beauty when exposed to light. Pink tourmaline occurs naturally and contains a diverse variety of elements, with most jewelry-quality stones consisting primarily of the mineral elbaite.
Opal formation is a unique geological process. Several varieties exist, each with distinct origins and characteristics. Fire opal, known for its vibrant red, orange, or yellow backgrounds, is primarily sourced from Mexico, with significant deposits emerging only in the mid-nineteenth century. Crystal opal, prized for its transparency and superior play-of-color, is also found in various locations. Water opal, a more subtle and affordable option, can be colorless or exhibit light base colors, and may or may not display play-of-color. Boulder opal uniquely combines precious opal with portions of the host rock, enhancing its durability. Assembled opal, a more affordable alternative, consists of opal slices adhered to a backing.
Gemological Properties
Pink tourmaline typically measures 7 to 7.5 on the Mohs hardness scale, making it a relatively durable gemstone, though not as hard as a pink sapphire. It is available in a wide array of pink hues, ranging from light pink to reddish pink. Tourmaline, in general, is known for its occurrence in many different colors, with some crystals displaying multiple colors, known as watermelon tourmaline.
Opal’s gemological properties are more complex due to its diverse varieties. The defining characteristic of many opals is “play-of-color,” a shifting display of rainbow hues. This phenomenon is not a major value factor in fire opal, which derives its value from the evenness and vibrancy of its base color. Crystal opal is renowned for its transparency and superior play-of-color effects, while water opal exhibits subtler color flashes. Opal’s relative softness makes it more susceptible to damage, and boulder opal, which retains some host rock, is more resilient.
Here's a table summarizing the key gemological properties:
| Gemstone | Chemical Formula | Hardness (Mohs) | Color | Play-of-Color |
|---|---|---|---|---|
| Pink Tourmaline | Complex Borosilicate | 7-7.5 | Light to Reddish Pink | No |
| Opal | Hydrated Silica | 5.5-6.5 | Varies widely; White, Black, Fire | Often Present |
| Fire Opal | Hydrated Silica | 5.5-6.5 | Red, Orange, Yellow | Absent |
| Crystal Opal | Hydrated Silica | 5.5-6.5 | Transparent with varied color flashes | Present |
| Water Opal | Hydrated Silica | 5.5-6.5 | Colorless or light base colors | Subtle |
Symbolism and Metaphysical Beliefs
Pink tourmaline is associated with positive energies, including friendship, compassion, self-love, and transformation. It is believed to help restore relationships, repair broken hearts, and instill a love for humanity. Some believe tourmaline possesses probiotic powers, aiding digestion and boosting the immune system, and that rubbing the stone creates an electrical charge.
Opal has carried diverse symbolic meanings throughout history. Ancient cultures attributed prophetic abilities and protection from disease to the stone. In modern times, opal is often associated with creativity, inspiration, and emotional expression. It is also the traditional stone given to celebrate the 14th wedding anniversary.
Care and Cleaning
Due to its hardness, pink tourmaline is relatively durable and can be cleaned with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and harsh chemicals.
Opal, being softer than tourmaline, requires more delicate care. It is susceptible to scratching and should be protected from impacts. Cleaning opal involves wiping it gently with a soft cloth and mild soapy water. Avoid ultrasonic cleaners, harsh chemicals, and prolonged exposure to heat or sunlight, as these can cause cracking or fading. Boulder opal, with its host rock matrix, is somewhat more durable.
Conclusion
Pink tourmaline and opal both represent the beauty and diversity of the October birthstones. Pink tourmaline, with its gentle energy and range of pink hues, has become a popular modern choice, while opal, steeped in history and renowned for its play-of-color, continues to enchant gemstone enthusiasts. Whether chosen for their aesthetic appeal, symbolic meaning, or geological origins, these gemstones offer a captivating connection to the natural world and a vibrant celebration of those born in October.