August and July each boast captivating birthstones steeped in history and symbolism. While July is traditionally represented by the ruby, August offers a trio of choices: peridot, sardonyx, and spinel. This article will delve into the geological origins, historical significance, and gemological properties of these vibrant gemstones, with a particular focus on peridot and ruby, as well as the more recently recognized spinel.
The practice of associating gemstones with specific months has evolved over time. Initially linked to the twelve stones in the breastplate of the High Priest of Israel, the modern birthstone list began to take shape in 1912 with the American National Retail Jewelers Association, and continues to be refined with additions like spinel. This evolution reflects both historical tradition and the evolving preferences within the jewelry industry.
A History of Significance
Sardonyx holds the distinction of being the original August birthstone, with a history stretching back over 4,000 years. However, peridot gained prominence in more recent times, and spinel was officially added to the list in 2016, offering a wider selection for those born in August. The ruby, a gem associated with passion and vitality, has long been the birthstone for July.
Historical accounts often blur the lines between gemstones. For instance, the famed “emeralds” adorning the Shrine of the Three Holy Kings in Germany’s Cologne Cathedral are, in fact, peridot. Similarly, some historians speculate that Cleopatra’s celebrated emerald collection may have largely consisted of this vibrant green gem. This confusion stemmed from the visual similarities between peridot and other green gemstones, such as emerald and topaz.
The recognition of spinel as an August birthstone is a more recent development. For centuries, red spinel was often mistaken for ruby, a gem with which it shares a similar hue. Only with advancements in gemological testing were the distinct properties of spinel fully understood, leading to its independent recognition and inclusion on the modern birthstone chart.
Geological Formation and Sources
Peridot, a variety of the mineral olivine, is formed under extreme conditions. It is often found in hardened lava, carried from deep within the Earth’s mantle, and has even been discovered in meteorites originating from outer space. The yellowish-green to greenish-yellow color of peridot is a defining characteristic.
Rubies, known for their intense red color, are formed in metamorphic rocks. Their color is derived from the presence of chromium.
Spinel, while often found alongside rubies, forms in different geological environments, typically in metamorphic rocks and alluvial deposits.
While specific mining locations aren’t detailed in the provided sources, the gems’ origins are linked to volcanic activity and metamorphic processes.
Gemological Properties
Peridot possesses a refractive index ranging from 1.65 to 1.69, a birefringence of 0.035 to 0.038, and a specific gravity of 3.34. Its Mohs hardness falls between 6.5 and 7, making it relatively durable but susceptible to scratching from harder materials.
Ruby, famed for its vibrant red hue, is also a durable gemstone, registering a 9 on the Mohs hardness scale. This hardness contributes to its brilliance and suitability for everyday wear.
Spinel’s properties are not detailed in the provided sources beyond its recent recognition as a birthstone.
The following table summarizes the key gemological properties of peridot:
| Property | Value |
|---|---|
| Mineral | Olivine |
| Color | Yellowish Green |
| Refractive Index | 1.65 - 1.69 |
| Birefringence | 0.035 - 0.038 |
| Specific Gravity | 3.34 |
| Mohs Hardness | 6.5 - 7 |
Symbolism and Metaphysical Beliefs
Birthstones are often imbued with symbolic meanings and metaphysical properties. Peridot is associated with abundance, protection, and positivity. The ruby, representing passion and vitality, is believed to inspire courage and confidence. While the sources do not detail specific metaphysical beliefs associated with spinel or sardonyx, birthstones generally carry cultural significance and are believed to influence the wearer’s well-being.
The association of birthstones with the twelve tribes of Israel further reinforces their historical and spiritual significance. The practice of wearing birthstones is thought to bring good luck and offer protection to those born in the corresponding month.
Popularity and Regional Trends
Peridot is the most common August birthstone, appearing in 38 states as the most frequently found gem. Ruby is the most common July birthstone, prevalent in 11 states. Sapphire is the most common September birthstone, found in Hawaii, while emerald is the most common May birthstone, found in Wyoming.
Amethyst is the rarest February birthstone, appearing in 47 states. Diamond is the rarest in Arizona, Louisiana, and Mississippi. These regional trends, based on state-level data, highlight the varying geological landscapes and gemstone availability across the United States.
Modern vs. Traditional Choices
The birthstone chart has evolved over time, with modern additions like spinel, citrine, and tanzanite supplementing the traditional list. Today, individuals often choose from both the modern and traditional options, selecting the stones that resonate with their personal preferences. The availability and cost of gemstones also influence these choices, with some traditional stones being more readily accessible or affordable than their modern counterparts.
July’s Fiery Ruby
The ruby, the traditional birthstone for July, is a symbol of passion, courage, and vitality. Its intense red color has captivated cultures for centuries, representing love, energy, and protection. The ruby’s durability, registering a 9 on the Mohs hardness scale, makes it a suitable gemstone for everyday wear. It is associated with the zodiac sign of Cancer (June 21 – July 22) and Leo (July 23 – August 22), complementing their respective personalities.
Care and Cleaning
Due to its Mohs hardness of 6.5 to 7, peridot requires careful handling to avoid scratches. Cleaning can be done with warm, soapy water and a soft brush. Avoid harsh chemicals and ultrasonic cleaners, as these can damage the gemstone.
Rubies, being more durable, can withstand more rigorous cleaning methods. However, it is still advisable to use warm, soapy water and a soft brush to maintain their brilliance.
Conclusion
The birthstones of July and August – ruby, peridot, and spinel – represent a diverse range of colors, histories, and symbolic meanings. From the fiery passion of the ruby to the vibrant green of peridot and the recently recognized beauty of spinel, these gemstones offer a captivating glimpse into the world of gemology and the enduring allure of natural beauty. The evolution of the birthstone list reflects both historical tradition and modern preferences, providing a wealth of choices for those seeking a meaningful and personalized gemstone.