October is a unique month in the world of birthstones, distinguished by having two officially recognized gems: opal and pink tourmaline. While opal holds a longer historical association with the month, pink tourmaline was formally added as an alternative in the 20th century, and now shares equal priority in recent American lists. Both gemstones are celebrated for their vibrant colors and captivating optical phenomena, reflecting the symbolism of fulfillment and the cyclical nature of life associated with the autumn season. This article will delve into the history, geological origins, gemological properties, and cultural significance of these two remarkable October birthstones.
History and Lore
The story of October birthstones is one of evolving tradition. Early associations with gemstones were often linked to zodiac signs rather than specific calendar months. However, the formalized system of birthstones began to take shape in the 19th century. Tiffany & Co. published birthstone poems in 1870, initially featuring opal as the sole gem for October. The National Association of Jewellers (now Jewellers of America) standardized a list in 1912, designating opal as the primary October birthstone and tourmaline as its alternative. This distinction was further refined in the 1950s when the Jewellery Industry Council of America specifically named pink tourmaline as the alternative. The most recent American list, from 2016, recognizes both opal and pink tourmaline equally, while the UK list from 2013 continues to recognize only opal.
Opal’s history is steeped in ancient mythology. Ancient Greeks believed opals were formed from the tears of joy shed by Zeus after defeating the Titans. Indigenous Australian lore also features prominent origin myths. One story describes the Rainbow Serpent, a powerful creator being, whose iridescent scales fell to earth as opals. Another myth recounts a Creator spirit traveling to earth on a rainbow, with opals emerging wherever their feet touched the ground. These myths highlight the association of opal with vibrant color and divine origins.
Tourmaline’s history, while less ancient in its specific association with October, is equally rich. The name “tourmaline” is derived from the Sinhalese word toramalli, meaning “finger of color,” a testament to the gem’s diverse range of hues. While not explicitly detailed in the provided sources, the gem has been valued for centuries across various cultures.
Geological Formation and Sources
The sources detail that both opal and tourmaline are known for their diverse range of colors and unique appearances. Opal formation is a unique geological process. It is formed from silica-rich water that seeps into cracks and voids in the earth, depositing microscopic spheres of silica. The arrangement of these spheres determines the play-of-color, the characteristic iridescent effect that makes opal so prized.
Tourmaline, on the other hand, forms in igneous and metamorphic rocks. The sources do not specify particular mining locations, but the gem is known to be found in various parts of the world, including Brazil, Africa, and the United States. The diverse chemical composition of tourmaline leads to a wide spectrum of colors, with pink tourmaline deriving its hue from the presence of manganese.
Gemological Properties
Opal is a hydrated amorphous form of silica, with a chemical composition of SiO₂·nH₂O. The sources do not provide a specific refractive index or density for opal. However, they do highlight its unique optical property: play-of-color. This phenomenon is caused by the diffraction of light as it passes through the microscopic silica spheres within the gem.
Tourmaline, specifically pink tourmaline, is a complex borosilicate mineral. The sources do not provide a chemical formula or specific refractive index for tourmaline. However, they mention that tourmaline is known as a “stone of mixed colors,” indicating a diverse chemical composition that results in a wide range of hues. The Mohs hardness of topaz, a November birthstone, is provided as 8, offering a comparative benchmark for gemstone durability.
Here's a table summarizing the limited gemological data available from the sources:
| Gemstone | Chemical Composition | Hardness (Mohs) | Key Property |
|---|---|---|---|
| Opal | SiO₂·nH₂O | Not specified | Play-of-color |
| Pink Tourmaline | Complex borosilicate | Not specified | Diverse color range |
Symbolism and Metaphysical Beliefs
Both opal and tourmaline carry symbolic weight. Opal, with its association with rainbows and ancient myths, is often linked to hope, purity, and truth. The sources mention that October symbolizes fulfillment and the life cycle, aligning with opal’s vibrant and multifaceted nature.
Pink tourmaline is said to boost energy, encourage love, and help smooth relationship troubles. This aligns with its association with Libra, a zodiac sign that values balance and harmony. The sources do not detail other metaphysical beliefs associated with either gem, but their vibrant colors and unique optical properties have undoubtedly contributed to their perceived powers throughout history.
Care and Cleaning
The sources do not provide specific care instructions for opal or tourmaline. However, given opal’s hydrated nature, it is generally recommended to avoid prolonged exposure to heat or dryness, as this can cause cracking. Tourmaline, being a relatively durable gemstone, can be cleaned with warm soapy water and a soft brush.
Conclusion
Opal and pink tourmaline represent a fascinating duality in the world of October birthstones. Opal, with its ancient origins and captivating play-of-color, embodies a rich history and enduring mystique. Pink tourmaline, a more recent addition to the October birthstone family, offers a vibrant and energetic alternative. Both gems symbolize the beauty and abundance of the autumn season, making them cherished gifts for those born in the tenth month. The evolution of their recognition as birthstones reflects the changing traditions and evolving appreciation for these remarkable gemstones.