December, the final month of the calendar year, is uniquely distinguished by its rich array of birthstones. Unlike months that are typically associated with a single gemstone, December features multiple stones—each with its own history, symbolism, and gemological properties. This diversity allows individuals born in December to choose a gem that resonates most with their personal style and spiritual or cultural preferences.
This article delves into the five recognized birthstones of December—turquoise, zircon, topaz, tanzanite, and lapis lazuli—examining their origins, properties, cultural significance, and care requirements. By exploring these stones in depth, we uncover the reasons behind their selection as December birthstones and how they continue to hold relevance in both historical and contemporary contexts.
History and Lore
The tradition of assigning gemstones to specific months has roots in ancient civilizations. The earliest known record of birthstones is found in the Bible, in Exodus 28:15–30, which describes the breastplate of Aaron, a sacred garment adorned with 12 gemstones representing the 12 tribes of Israel. Over time, these stones were linked to the months of the year and later to zodiac signs.
By the 18th and 19th centuries, the birthstone tradition had evolved into a more structured format. In 1870, Tiffany & Co. published a set of "Gregorian Birthstone Poems" that first associated turquoise with December. In 1912, the National Association of Jewellers (now the Jewelers of America) formalized the list, including turquoise and lapis lazuli as December’s primary and alternative birthstones.
The list continued to evolve throughout the 20th century. In 1952, zircon was added by the Jewelry Industry Council of America. Nearly five decades later, in 2002, tanzanite was officially recognized as a December birthstone in the United States. This expansion reflects not only the changing tastes in jewelry but also the discovery of new gemstones and the growing appreciation for their unique characteristics.
The inclusion of multiple birthstones for December serves practical and symbolic purposes. It offers a range of colors, from deep blues to vibrant purples, catering to different aesthetic preferences and budgets. Additionally, each gemstone carries its own set of symbolic meanings, allowing individuals to select a stone that aligns with their personal beliefs and experiences.
Geological Formation and Sources
Each of December’s birthstones is formed under distinct geological conditions and is found in specific regions around the world.
Turquoise
Turquoise is a hydrated phosphate of aluminum and copper, formed in arid environments where copper deposits come into contact with water. It is typically found in veins within the host rock, often in association with other minerals such as quartz and pyrite.
The most famous sources of turquoise are in the southwestern United States, particularly in New Mexico and Arizona. However, turquoise is also mined in Iran, China, Egypt, and Mexico. The American Southwest is especially renowned for its high-quality turquoise, which has been used by Native American tribes for centuries in jewelry and ceremonial objects.
Zircon
Zircon is a zirconium silicate that occurs in a wide range of colors, including red, yellow, green, and blue. The blue zircon most commonly associated with December is created through heat treatment, which alters the crystal structure and produces its vibrant hue.
Zircon is found in a variety of geological settings, including igneous, metamorphic, and sedimentary rocks. Major sources include Sri Lanka, Madagascar, Thailand, and Australia. Zircon’s durability and brilliance make it a popular alternative to diamonds and other precious gemstones.
Topaz
Topaz is a silicate mineral composed primarily of aluminum and fluorine. It is known for its clarity and range of colors, including yellow, orange, pink, and blue. Blue topaz, the most popular variety for December, is typically created through irradiation and heat treatment.
Topaz is found in igneous and metamorphic rocks, often in association with quartz and other minerals. Major sources include Brazil, Mexico, Nigeria, and the United States. The gemstone is prized for its hardness and affordability, making it an excellent choice for everyday jewelry.
Tanzanite
Tanzanite is a rare blue to violet variety of the mineral zoisite. It is only found in one location in the world—near Mount Kilimanjaro in Tanzania. This geographical exclusivity contributes to its high value and allure.
Tanzanite was first discovered in the 1960s and quickly became a popular gemstone due to its striking color and the fact that it was named after its country of origin. Its color can vary depending on the angle of light, and it is typically treated to enhance its color and clarity.
Lapis Lazuli
Lapis lazuli is a metamorphic rock composed primarily of lazurite, with varying amounts of other minerals such as pyrite and calcite. It is known for its deep blue color and golden flecks of pyrite.
Lapis lazuli is primarily mined in Afghanistan, where it has been used for thousands of years in jewelry, sculpture, and even in cosmetics. Other sources include Russia, Argentina, and Canada. Its historical use by royalty and artists, particularly in ancient Egypt and Mesopotamia, has contributed to its enduring appeal.
Gemological Properties
Understanding the gemological properties of December’s birthstones is essential for both collectors and consumers. These properties determine not only the appearance and durability of the stones but also their suitability for different types of jewelry.
Turquoise
- Chemical Composition: Hydrated phosphate of aluminum and copper (Al₂(Cu,Fe)₂(PO₄)₂(OH)₂·nH₂O)
- Hardness (Mohs Scale): 5–6
- Color: Ranges from blue to green, often with matrix patterns
- Luster: Waxy to dull
- Refractive Index: 1.61–1.65
- Specific Gravity: 2.6–2.8
Turquoise is relatively soft compared to other gemstones, making it susceptible to scratches and damage from harsh chemicals. It also absorbs oils and dirt easily, requiring gentle cleaning and protection from prolonged exposure to sunlight.
Zircon
- Chemical Composition: Zirconium silicate (ZrSiO₄)
- Hardness (Mohs Scale): 6.5–7.5
- Color: Available in a wide range of colors, including blue, yellow, red, and green
- Luster: Vitreous to adamantine
- Refractive Index: 1.92–2.01
- Specific Gravity: 4.6–4.8
Zircon is known for its high refractive index and dispersion, which gives it a brilliant sparkle. Blue zircon, in particular, is popular for its similarity to diamonds and cubic zirconia. It is a durable gemstone that can withstand daily wear, provided it is free of inclusions that may affect its strength.
Topaz
- Chemical Composition: Aluminum silicate fluoride hydroxide (Al₂SiO₄(F,OH)₂)
- Hardness (Mohs Scale): 8
- Color: Available in a wide range of colors, including blue, yellow, pink, and white
- Luster: Vitreous
- Refractive Index: 1.61–1.63
- Specific Gravity: 3.4–3.6
Topaz is one of the hardest gemstones, making it ideal for use in rings and other jewelry that is worn frequently. Its clarity and brilliance, combined with its affordability, have made it a popular choice in both classic and modern designs.
Tanzanite
- Chemical Composition: Calcium aluminum silicate hydroxide (Ca₂Al₃(SiO₄)(OH)₆)
- Hardness (Mohs Scale): 6–7
- Color: Blue to violet, often with pleochroism
- Luster: Vitreous
- Refractive Index: 1.694–1.701
- Specific Gravity: 3.3–3.4
Tanzanite is a relatively new gemstone in the jewelry world, and its softness compared to other birthstones means it requires careful handling. It is often used in pendants and earrings rather than in rings, where it is less likely to be subjected to impact or abrasion.
Lapis Lazuli
- Chemical Composition: Metamorphic rock primarily composed of lazurite, with pyrite and calcite
- Hardness (Mohs Scale): 5–6
- Color: Deep blue with flecks of gold and white
- Luster: Waxy to dull
- Refractive Index: Varies due to composition
- Specific Gravity: 2.4–2.9
Lapis lazuli is a composite material rather than a single mineral, which affects its hardness and durability. It is best suited for use in pendants, brooches, and other low-wear pieces. Like turquoise, it requires gentle cleaning and protection from chemicals and sunlight.
Symbolism and Metaphysical Beliefs
December’s birthstones have long been associated with various spiritual, emotional, and metaphysical properties, reflecting the beliefs and traditions of different cultures.
Turquoise
Turquoise has been revered for its protective and healing properties for thousands of years. Ancient Egyptians used it in amulets to ward off evil and promote health. Native American tribes, particularly the Navajo and Zuni, have used turquoise in ceremonial jewelry and as a symbol of good fortune and spiritual connection.
In modern metaphysical practices, turquoise is believed to enhance communication, promote emotional balance, and stimulate the throat chakra. It is also associated with the zodiac sign Sagittarius and is considered a stone of wisdom and adventure.
Zircon
Zircon is often linked to transformation and renewal. Its rainbow-like dispersion and fire have made it a symbol of joy, clarity, and spiritual awakening. In some traditions, zircon is believed to enhance intuition and promote emotional healing.
Blue zircon, in particular, is associated with calmness and emotional stability. It is often used in meditation and energy work to help clear the mind and connect with higher states of consciousness.
Topaz
Topaz has long been associated with strength and protection. In ancient times, it was believed to bring courage and ward off nightmares. Blue topaz is especially valued for its calming effects, making it a popular choice for those seeking emotional balance and mental clarity.
In Hindu tradition, topaz is considered a powerful stone that enhances self-esteem, encourages learning, and aligns the body's energy meridians. It is also believed to promote spiritual growth and emotional stability.
Tanzanite
Tanzanite is often referred to as the “stone of transition,” as it is believed to support emotional healing and personal transformation. It is associated with the heart and throat chakras, helping individuals express their emotions and communicate more effectively.
Tanzanite is also believed to enhance intuition and spiritual awareness. Its rarity and beauty make it a powerful symbol of uniqueness and individuality.
Lapis Lazuli
Lapis lazuli has a long history of use in spiritual and artistic contexts. In ancient Egypt, it was used in the adornment of pharaohs and was believed to bring wisdom and protection. It is also associated with the third eye chakra, enhancing intuition, psychic abilities, and spiritual insight.
Lapis lazuli is believed to promote self-mastery, stress relief, and mental clarity. It is often used in meditation and is considered a stone of deep wisdom and emotional balance.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of December’s birthstones. Each gemstone has specific requirements based on its hardness, composition, and sensitivity to environmental factors.
Turquoise
Turquoise is relatively soft and porous, making it susceptible to damage from harsh chemicals, oils, and heat. It should be cleaned with a soft cloth and mild soap. Avoid soaking it in water or exposing it to direct sunlight for extended periods.
Turquoise should be stored separately from other gemstones to prevent scratches. It is also advisable to avoid wearing turquoise in environments where it may be exposed to harsh chemicals or abrasives.
Zircon
Zircon is a durable gemstone, but it can be sensitive to heat and sudden temperature changes. It is best cleaned with a soft brush and warm, soapy water. Ultrasonic cleaners can be used with caution, but steam cleaning is not recommended.
Zircon should be stored in a dry, cool place to prevent any potential damage from heat or humidity.
Topaz
Topaz is a hard and durable gemstone, making it suitable for everyday wear. It can be cleaned with a soft cloth, warm water, and mild detergent. Ultrasonic and steam cleaners are generally safe for topaz, provided the stone is free of inclusions that could be affected by these methods.
Topaz should be stored in a secure place to prevent scratches from other gemstones.
Tanzanite
Tanzanite is a relatively soft gemstone and requires gentle handling. It should be cleaned with a soft cloth and mild soap, avoiding harsh chemicals and abrasive materials. Ultrasonic and steam cleaners can be used with care, but caution is advised due to the potential for damage from heat and pressure.
Tanzanite should be stored separately from other gemstones to avoid scratches and exposure to direct sunlight.
Lapis Lazuli
Lapis lazuli is a composite material and can be easily damaged by harsh chemicals and abrasives. It should be cleaned with a soft cloth and mild soap. Avoid using ultrasonic or steam cleaners, as these can cause the stone to lose its luster.
Lapis lazuli should be stored in a cool, dry place to prevent any damage from moisture or heat.
Conclusion
December’s birthstones—turquoise, zircon, topaz, tanzanite, and lapis lazuli—offer a remarkable diversity of colors, histories, and symbolic meanings. Each gemstone carries a unique legacy, from ancient traditions to modern interpretations, making them more than just beautiful adornments.
The evolution of December’s birthstone list reflects the dynamic nature of gemology and the enduring appeal of these stones. Whether chosen for their color, durability, or metaphysical properties, these gemstones continue to captivate and inspire. For those born in December, they offer a meaningful and personal connection to the past, present, and future.
Understanding the properties, history, and care of these gemstones allows collectors, jewelry wearers, and gemstone enthusiasts to appreciate their value and significance. As the final month of the year, December’s birthstones serve as a fitting tribute to the rich and enduring legacy of gemstones in human culture.