The month of August is unique in its association with not one, but three recognized birthstones: spinel, sardonyx, and peridot (though peridot is not mentioned in the provided sources). These gemstones, each possessing distinct characteristics and a rich history, offer a diverse palette of choices for those seeking a meaningful adornment. While spinel has gained prominence in recent years, particularly with a 2007 discovery in Tanzania yielding vibrant pink and orange hues, sardonyx holds the distinction as the most ancient of the August birthstones. This article will delve into the history, geological origins, gemological properties, and symbolism surrounding spinel and sardonyx, drawing exclusively from the provided sources.
History and Lore
The tradition of associating gemstones with specific months dates back millennia. Early connections can be traced to the Breastplate of Aaron, described in the Book of Exodus, where twelve gemstones represented the tribes of Israel. Over time, various cultures developed their own birthstone lists, leading to some variation in modern interpretations. Birthstone names themselves have roots in ancient rituals and beliefs, with gemstones traditionally worn not only as adornments but also as forms of protection or to influence fortune.
Sardonyx, in particular, boasts a long and storied past. In ancient times, it was a favored material for Roman seals and signet rings, prized for its unique property of preventing hot wax from adhering to its surface. For centuries, the distinctive banded patterns of sardonyx – alternating layers of brownish-red sard and white or black onyx – made it a popular choice for carving cameos and intaglios.
The 20th century saw efforts to standardize birthstone lists. A formalized chart emerged in 1912, though regional and era-specific variations continue to exist. The mid-20th century also witnessed significant marketing and promotion of birthstones, notably through initiatives like Harry Winston’s “Court of Jewels” exhibition (1949-1953), which showcased museum-quality historical gems, including birthstones. The latter half of the 20th century also saw a shift towards more minimalist jewelry designs, exemplified by Tiffany & Co.’s “Diamonds by the Yard” collection, demonstrating the enduring appeal of gemstone adornment.
Geological Formation and Sources
Sardonyx is a variety of chalcedony, a cryptocrystalline form of quartz. It is formed through the layering of sard and onyx, resulting in its characteristic banded appearance. The sources for sardonyx are not explicitly detailed in the provided materials.
Spinel, however, is noted to be sourced from Tanzania, with significant discoveries made in 2007. These Tanzanian mines produce spinel in a range of colors, including pinkish and orangy-red, as well as purple and blue hues. The sources do not provide a comprehensive list of spinel mining locations beyond Tanzania.
Gemological Properties
Spinel exhibits a hardness of 8 on the Mohs scale, making it a durable gemstone suitable for everyday wear, including in rings. It is generally stable when exposed to light and chemicals. However, exposure to high heat can cause fading in some colors of spinel. Cleaning can be performed using ultrasonic or steam cleaners, but caution is advised, particularly if the stone contains fractures. Warm soapy water and a soft-bristle brush are always a safe alternative.
Sardonyx, being a form of chalcedony, shares the properties of quartz. The sources do not provide specific details regarding its hardness or chemical composition. However, its banded structure is a defining characteristic, resulting from the alternating layers of sard and onyx.
The following table summarizes the gemological properties of spinel as provided in the sources:
| Property | Spinel |
|---|---|
| Hardness (Mohs) | 8 |
| Stability to Light | Stable |
| Stability to Chemicals | Stable |
| Heat Sensitivity | Some colors fade |
| Cleaning | Ultrasonic/Steam (with caution), Warm Soapy Water |
Symbolism and Metaphysical Beliefs
The provided sources highlight the symbolic significance of birthstones in general, noting that each gem carries storied symbolism, from special protections to good fortune. Gemstones were historically believed to protect, calm, or guide the wearer, and these beliefs continue to influence how birthstones are perceived today.
Specifically, garnet, January’s birthstone, is associated with trust and friendship. Red coral, also a January birthstone, is linked to tranquility and clarity. Amethyst, the traditional February birthstone, represents wisdom, while Charoite, Purple Spiny Oyster Shell, and Sugilite, southwestern alternatives, offer a palette rooted in royalty. Turquoise, a southwestern birthstone, is revered for its earthy hues and timeless beauty.
While the sources do not detail specific symbolism for spinel or sardonyx, they emphasize the broader tradition of attributing meaning and power to gemstones. Emeralds, the May birthstone, are associated with hope, prosperity, and serenity, illustrating the types of qualities historically linked to these stones.
Care and Cleaning
As previously mentioned, spinel is a durable gemstone suitable for various jewelry settings due to its hardness of 8 on the Mohs scale. Cleaning can be approached with caution using ultrasonic or steam cleaners, but warm soapy water is always the safest option, especially if the stone exhibits fractures.
Specific care instructions for sardonyx are not provided in the sources. However, given its composition as a form of chalcedony, similar gentle cleaning methods would likely be appropriate.
Conclusion
The August birthstones, spinel and sardonyx, represent a fascinating intersection of history, geology, and symbolism. Sardonyx, with its ancient origins and distinctive banded patterns, evokes a sense of timeless elegance. Spinel, particularly the vibrant discoveries from Tanzania, offers a more contemporary appeal. Both gemstones, while differing in their properties and origins, share a common thread: they are more than just colored stones; they are symbolic personal signatures, rich with meaning and connection to the past. The enduring popularity of birthstones, as evidenced by their continued use in jewelry and their presence in museum-quality collections, underscores their lasting significance in human culture.