For centuries, spinel has been a gemstone shrouded in mistaken identity, often confused with its more famous cousin, ruby. Today, however, spinel is recognized as a gemstone in its own right, celebrated for its vibrant colors and rich history. While historically associated with August as a birthstone, it also shares the honor with opal as an October birthstone. This article will delve into the fascinating world of spinel, exploring its geological origins, historical significance, gemological properties, and the lore surrounding this captivating gem.
History and Lore
The story of spinel is inextricably linked to that of ruby. For centuries, particularly before advancements in gemological testing, red spinel was frequently mistaken for ruby. This misidentification led to some of history’s most celebrated “rubies” actually being spinel. A prime example is the approximately 170-carat Black Prince’s “ruby,” a centerpiece of Great Britain’s Imperial State Crown. This stone, owned by successive Moorish and Spanish kings before being acquired by Edward, the Black Prince, in 1367, was not recognized as spinel until the 18th century, when chemical differences were definitively established.
The name “spinel” itself originates from the Latin word spina, meaning thorn, a reference to the sharp, pointed crystals in which the gem is often found. While its true identity remained obscured for a long time, spinel has a history stretching back millennia. Red spinel, along with other red gems, was historically believed to be a remedy for blood loss and inflammatory diseases, and to ease anger and promote harmony. It is traditionally given as a gift to celebrate the 22nd wedding anniversary.
The recognition of spinel as a distinct gemstone gained momentum in the 19th century, and today, it is appreciated for its own unique qualities and beauty. The discovery of significant deposits in locations like Tajikistan and Myanmar further fueled its rise in popularity.
Geological Formation and Sources
Spinel forms under extreme geological conditions, often found in metamorphic rocks and alluvial deposits. Major sources of spinel include Tajikistan, Myanmar, Sri Lanka, Vietnam, Tanzania, and Pakistan. Certain locations are renowned for producing spinel of particularly striking colors. For instance, Myanmar is known for its hot pink and red spinel varieties.
The gem is a mineral composed of magnesium aluminum oxide (MgAl2O4), with trace elements contributing to its diverse range of colors. While red spinel is perhaps the most well-known, the gem occurs in a wealth of hues, including vibrant pink, orange, purple, violet, blue, and bluish-green.
Gemological Properties
Spinel boasts a number of desirable gemological properties. Its hardness measures 8 on the Mohs scale, making it a durable gemstone suitable for all types of jewelry. The gem exhibits a single refractive index, ranging from 1.712 to 1.762, and displays a vitreous luster.
Here's a table summarizing key gemological properties:
| Property | Value |
|---|---|
| Chemical Formula | MgAl₂O₄ |
| Mohs Hardness | 8 |
| Refractive Index | 1.712 - 1.762 |
| Luster | Vitreous |
| Crystal System | Isometric |
Spinel is transparent, and its colors are due to trace elements within its crystal structure. Chromium is responsible for the red hues, while iron and titanium contribute to the blue shades. The gem’s brilliance is particularly noteworthy, rivaling that of other popular gemstones.
Symbolism and Metaphysical Beliefs
Throughout history, spinel has been imbued with symbolic meaning. Red spinel was traditionally associated with vitality and protection, believed to offer remedies for various ailments. The gem was thought to ease anger and promote harmony among those who wore it.
While specific metaphysical beliefs vary, spinel is often associated with revitalization, hope, and the encouragement of passion. It is considered a stone that can help overcome challenges and promote positive energy.
Care and Cleaning
Due to its hardness of 8 on the Mohs scale, spinel is a relatively durable gemstone. However, like all jewelry, it requires proper care to maintain its brilliance. Spinel can be safely cleaned using warm, soapy water and a soft brush. Avoid harsh chemicals, ultrasonic cleaners, and steam cleaners, as these can potentially damage the stone. It is also advisable to store spinel jewelry separately from other gemstones to prevent scratching.
Opal: The October Alternative
Opal, the other birthstone for October, is a mineraloid – meaning it lacks a crystalline structure – formed by the gradual heating of silica gel found in rock cracks. It is valued for its “play-of-color,” a shifting display of rainbow hues under white light. The origin of the name “opal” is debated, with some tracing it to the Sanskrit word upala, meaning “precious stone,” while others connect it to the Ancient Greek opallios, meaning “to see a change in color.”
Historically, opal has been associated with various beliefs. Bedouins believed it held lightning, while ancient Greeks thought it bestowed the gift of prophecy and protection from disease. Europeans considered it a symbol of purity, hope, and truth. Opal is also the traditional stone given to celebrate the 14th wedding anniversary. Major sources of opal are not detailed in the provided sources.
Conclusion
Spinel, once overshadowed by its resemblance to ruby, has emerged as a gemstone of significant beauty and historical importance. Its vibrant colors, durability, and rich lore make it a prized possession for gem enthusiasts and jewelry lovers alike. Whether celebrated as an August or October birthstone, spinel represents a captivating blend of geological wonder and cultural significance. The story of spinel is a testament to the enduring allure of gemstones and the fascinating journey of discovery that continues to unfold within the world of gemology.