August boasts a trio of captivating birthstones: peridot, spinel, and sardonyx. While peridot and sardonyx have long held the association with this summer month, spinel has recently gained prominence as a modern August birthstone, recognized by the American Gem Trade Association (AGTA) in 2007. This gemstone, often mistaken for ruby or sapphire throughout history, possesses a brilliance and range of colors that have captivated gem enthusiasts and royalty alike. This article will delve into the history, geological origins, gemological properties, symbolism, and care of spinel, exploring why it is a worthy addition to the esteemed list of birthstones.
History and Lore
Spinel’s history is intertwined with that of other, more famous gemstones. For centuries, particularly before the 18th century, many spinels were misidentified as rubies. One of the most notable examples is the “Black Prince’s Ruby,” a 170-carat red spinel that has been part of the British Imperial State Crown since the 14th century. Originally owned by Moorish and Spanish kings, the stone was acquired by Edward, Prince of Wales, as payment for winning a battle. It wasn’t until advancements in gemological science allowed for accurate chemical distinction that this celebrated gem was correctly identified as spinel.
Other significant spinels have graced royal collections, including the Samarian Spinel, the largest known fine red spinel, and stones within the Iranian and Russian Imperial Crown Jewels. This association with royalty contributed to spinel’s prestige, even during periods when its true identity was unknown.
Beyond its regal connections, spinel also holds a place in folklore and traditional beliefs. Red spinel was believed to be a remedy for blood loss and inflammatory diseases. Vivid red spinel was thought to encourage harmony and symbolize vitality. During the Renaissance, it was worn by public speakers and orators, believed to bestow eloquence. Some traditions suggest it aided single women in attracting spouses and fostered happy marriages. A magnetic variety of spinel, known as lodestone, was even used by Cleopatra, who reportedly slept on it to maintain youthful skin.
Geological Formation and Sources
Spinel crystallizes in the isometric system, forming octahedral crystals. It is found in metamorphic rocks, particularly those subjected to high temperatures and pressures. It also occurs in alluvial deposits, having been weathered from its original host rocks.
Several locations around the world are known for producing spinel. Myanmar (Burma) is renowned for its vibrant hot pink and red spinels. Sri Lanka yields blue, pink, and purple varieties, often found in the rolling hills of the Central Highlands and river gravels of the Ratnapura District. Northern Vietnam, specifically the Luc Yen region, is a source of deep red, purple, pink, vivid blue, violet, and violet-blue spinels.
More recently, in 2007, Tanzania emerged as a significant source of pinkish and orangy-red spinel, adding to the gem’s growing availability. Other sources include Tajikistan and Pakistan.
Gemological Properties
Spinel’s chemical formula is (Mg,Fe)Al2O4, indicating it is composed of magnesium, iron, aluminum, and oxygen. It registers an 8 on the Mohs hardness scale, making it a durable gemstone suitable for everyday wear, including in rings. This hardness is greater than peridot, which scores a 6.5-7 on the Mohs scale.
Spinel exhibits a wide range of colors, including intense red, vivid pink, orange, purple, violet, blue, and bluish-green. The presence of trace elements, such as chromium, iron, and manganese, contributes to these varied hues. While red spinel is often compared to ruby, its refractive index and other optical properties differ, allowing gemologists to distinguish between the two.
Spinel is stable when exposed to light and chemicals. However, exposure to high heat can cause some colors to fade. It also possesses interesting magnetic properties; the lodestone variety is highly magnetic and historically used for magnetizing compass needles.
Here's a table summarizing key gemological properties:
| Property | Value |
|---|---|
| Chemical Formula | (Mg,Fe)Al2O4 |
| Hardness (Mohs) | 8 |
| Crystal System | Isometric |
| Luster | Vitreous |
| Refractive Index | Varies by color |
| Stability | Stable to light & chemicals |
| Special Feature | Some varieties are magnetic |
Symbolism and Metaphysical Beliefs
Beyond its historical and gemological significance, spinel is also associated with various symbolic meanings. Red spinel, in particular, is believed to encourage harmony and symbolize vitality. It is thought to stimulate passion and drive, while also promoting physical energy.
Different colors of spinel are attributed with unique properties. While specific metaphysical beliefs vary, the gem is generally considered to be a stone of renewal, offering protection and grounding energy. It is believed to help overcome challenges and promote positive transformation.
Care and Cleaning
Due to its hardness of 8 on the Mohs scale, spinel is a relatively durable gemstone. It can be cleaned using ultrasonic and steam cleaners, although caution should be exercised if the stone contains fractures. Warm, soapy water is always a safe and effective cleaning method. Regular cleaning will help maintain spinel’s brilliance and sparkle. It is advisable to store spinel jewelry separately from other gemstones to prevent scratching.
Conclusion
Spinel, once overshadowed by its more famous counterparts, has rightfully earned its place as a celebrated August birthstone. Its rich history, vibrant colors, durable nature, and intriguing lore make it a captivating gem for collectors, jewelry enthusiasts, and those born in the eighth month of the year. From adorning royal crowns to inspiring ancient beliefs, spinel continues to enchant with its beauty and enduring appeal. Its recent recognition as a modern birthstone ensures that this remarkable gem will continue to shine for generations to come.