Birthstones have fascinated humans for centuries, blending scientific wonder with cultural and spiritual significance. July and December each have richly symbolic and historically significant birthstones that reflect both the beauty and mystery of the natural world. For July, ruby reigns as the primary birthstone, while December offers a selection of three modern options—turquoise, tanzanite, and zircon—alongside its traditional gemstone, turquoise. This article delves into the geological origins, gemological properties, historical uses, cultural symbolism, and care instructions for these gemstones, all drawn from authoritative and reliable sources.
Introduction
July and December are months with rich birthstone traditions. The July birthstone, ruby, is celebrated for its fiery red hue and association with passion and power. December, on the other hand, has a more varied selection of birthstones, including turquoise, zircon, and tanzanite, each with its own distinct characteristics and historical significance. These gemstones are not only prized for their beauty but also for their enduring roles in jewelry, folklore, and spiritual practices.
The modern birthstone list has evolved over time, incorporating new discoveries and alternative options that cater to a broader range of preferences and budgets. In this article, we explore the scientific and cultural aspects of the July and December birthstones, providing readers with a comprehensive overview grounded in reliable data and historical context.
July Birthstone: Ruby
History and Lore
Ruby, the birthstone for July, is one of the most revered gemstones in history. Known for its deep red color and symbolic association with love and vitality, ruby has been cherished across cultures for millennia. In ancient India, ruby was called the “king of precious stones” due to its rarity, hardness, and beauty. It was believed to possess mystical powers that could predict danger and protect the wearer.
Medieval Europeans associated ruby with health, wisdom, and success in love. Burmese warriors wore ruby as a symbol of invincibility in battle. In addition to its historical significance, ruby is also a traditional gemstone for the 15th and 40th wedding anniversaries, underscoring its enduring value and romantic symbolism.
Geological Formation and Sources
Ruby is a variety of the mineral corundum, with its red coloration derived from trace amounts of chromium. The finest ruby, known as “pigeon’s blood,” is characterized by a deep red with a hint of purple. This gemstone is formed under high-pressure and high-temperature conditions deep within the Earth's crust. Major sources of ruby include Burma (Myanmar), Sri Lanka, Thailand, and Madagascar.
The geological process of ruby formation involves the crystallization of aluminum oxide (Al₂O₃) with chromium impurities. These conditions typically occur in metamorphic rocks, where heat and pressure transform existing minerals into new ones. The result is a gemstone of exceptional hardness, second only to diamond on the Mohs scale.
Gemological Properties
Ruby is renowned for its hardness (9 on the Mohs scale), brilliance, and deep red color. Its refractive index ranges from 1.76 to 1.78, and it has a specific gravity of approximately 4.00. The presence of inclusions, often referred to as “silk,” is common in ruby and can enhance its appearance by scattering light and giving it a velvety sheen.
Ruby is typically cut in round, oval, or cushion shapes to maximize its brilliance and color. The finest ruby specimens are heat-treated to improve clarity and color, a process that is widely accepted in the gem trade. Despite its hardness, ruby can be damaged by sudden temperature changes or exposure to harsh chemicals.
Symbolism and Metaphysical Beliefs
Ruby has long been associated with passion, courage, and vitality. In ancient times, it was believed to have the power to predict danger and protect the wearer from harm. In modern times, ruby is often worn to enhance confidence, emotional strength, and romantic energy. Some metaphysical traditions suggest that ruby stimulates the heart and circulatory system, promoting physical and emotional well-being.
Care and Cleaning
Due to its hardness, ruby is relatively durable and suitable for everyday wear. However, it should be cleaned with care to avoid damage. A soft cloth and mild soap solution are typically sufficient for cleaning ruby. Ultrasonic cleaners are generally safe, but steam cleaning should be avoided due to the potential for thermal shock.
Ruby should also be protected from sudden temperature changes and abrasive materials. When storing ruby jewelry, it is advisable to wrap the pieces in a soft cloth or place them in a padded jewelry box to prevent scratches.
December Birthstones: Turquoise, Tanzanite, and Zircon
History and Lore
December has a rich selection of birthstones, including turquoise, tanzanite, and zircon. Turquoise, the traditional December birthstone, has a long and storied history. Used in ancient Egypt, Mesopotamia, and Native American cultures, turquoise has long been associated with protection, healing, and spiritual connection. It was often used in amulets and talismans to ward off evil and bring good fortune.
Tanzanite, discovered in Tanzania in the 1960s, is a relatively modern gemstone. Its vibrant blue-violet color quickly made it a popular choice for jewelry. Zircon, another December birthstone, is a versatile gemstone that can display a range of colors, including blue, green, and brown. Zircon has been used in jewelry for centuries, though it has gained renewed attention in recent years for its affordability and beauty.
Geological Formation and Sources
Turquoise is a hydrated phosphate of aluminum and copper, with the chemical formula CuAl₆(PO₄)₄(OH)₈·4H₂O. It forms in arid environments where copper-rich rocks are exposed to water. Turquoise is typically found in weathered volcanic and sedimentary rocks, particularly in regions with a dry climate. Major sources include the United States, Iran, and China.
Tanzanite is a variety of the mineral zoisite, with its blue-violet coloration derived from trace amounts of vanadium. It is found only in Tanzania, making it one of the most exclusive gemstones in the world. The geological conditions required for tanzanite formation are rare, contributing to its limited supply and high value.
Zircon is a zirconium silicate with a wide range of colors, including blue, green, and brown. It is formed in igneous and metamorphic rocks and is found in many parts of the world, including Australia, Thailand, and the United States. Blue zircon, in particular, is popular for its vibrant color and affordability.
Gemological Properties
Turquoise is a relatively soft gemstone, with a hardness of 5 to 6 on the Mohs scale. It is porous and can easily be discolored by oils, pigments, and changes in moisture. Turquoise is often stabilized with resins or oils to enhance its durability and color.
Tanzanite has a hardness of 6 to 7 on the Mohs scale and a refractive index of 1.69 to 1.70. It is known for its strong pleochroism, meaning it can display different colors when viewed from different angles. Tanzanite is typically heat-treated to enhance its color, a process that is widely accepted in the gem trade.
Zircon has a hardness of 6 to 7.5 on the Mohs scale and a refractive index that varies depending on the color. Blue zircon, in particular, is prized for its brilliance and affordability. Zircon is often heat-treated to enhance its color and clarity.
Symbolism and Metaphysical Beliefs
Turquoise has long been associated with protection, healing, and spiritual connection. In ancient times, it was used in amulets and talismans to ward off evil and bring good fortune. In Native American cultures, turquoise is considered a sacred stone that connects the earth and sky. It is believed to promote calmness, clarity, and emotional balance.
Tanzanite is associated with transformation and spiritual growth. It is believed to enhance intuition and promote emotional healing. Zircon is often linked with prosperity and good fortune. In some cultures, zircon is believed to bring protection and enhance the wearer’s vitality and energy.
Care and Cleaning
Due to its softness and porosity, turquoise requires special care. It should be cleaned with a soft cloth and mild soap solution. Avoid exposing turquoise to oils, lotions, and perfumes, as these can discolor the stone. Turquoise should also be kept in a cool, dry place to prevent changes in color and moisture content.
Tanzanite is relatively durable but can be sensitive to heat and light. It should be cleaned with a soft cloth and mild soap solution. Avoid using ultrasonic or steam cleaners, as these can cause damage. Tanzanite should also be protected from sudden temperature changes and exposure to harsh chemicals.
Zircon is relatively durable and can be cleaned with a soft cloth and mild soap solution. Ultrasonic and steam cleaners are generally safe for zircon. However, it should be protected from sudden temperature changes and exposure to abrasive materials.
Conclusion
The birthstones of July and December—ruby, turquoise, tanzanite, and zircon—each possess unique geological, historical, and cultural significance. Ruby, with its deep red color and association with passion and vitality, continues to be a cherished gemstone for July. December, with its array of options, offers a range of choices that reflect both tradition and modernity.
Whether you prefer the fiery brilliance of ruby, the calming blue of turquoise, the vibrant blue-violet of tanzanite, or the versatile beauty of zircon, these gemstones offer something for every taste and occasion. Their enduring popularity is a testament to their beauty, symbolism, and the deep connections they foster between people and the natural world.
Understanding the properties, history, and care requirements of these gemstones allows you to appreciate their value and wear them with confidence. Whether as a gift or a personal treasure, these birthstones continue to inspire and captivate, bridging the past and present in the world of gemology.