December, the final month of the calendar year, is not only a time of celebration and reflection but also a month rich in gemological diversity. Individuals born in December are blessed with a rare opportunity—five distinct gemstones are officially recognized as their birthstones. These stones, each with its own unique color, history, and symbolism, reflect the multifaceted nature of December itself: a season of cold and warmth, of endings and new beginnings.
The December birthstones—zircon, topaz, tanzanite, lapis lazuli, and turquoise—offer a spectrum of options that vary in color, hardness, and cultural significance. While turquoise and zircon have long been considered the primary December birthstones, the inclusion of tanzanite in the 2002 revision of the birthstone list, and the recognition of topaz and lapis lazuli as traditional choices, has expanded the selection to reflect both historical and contemporary tastes.
This article delves into the properties, origins, symbolism, and care of these December birthstones, drawing from authoritative and historical sources to provide a comprehensive and insightful overview.
History and Lore
The tradition of assigning gemstones to months of the year is an ancient one, with roots in both biblical and cultural practices. According to some of the earliest references, such as the "Gregorian Birthstone Poems" published by Tiffany & Co. in 1870, turquoise was designated as the December birthstone. This early designation was likely influenced by the gemstone’s deep blue-green hues, which mirror the colors of winter and have long been associated with protection and good fortune.
By 1912, the list was expanded by the National Association of Jewellers (now Jewellers of America), which included lapis lazuli as an alternative December birthstone. Lapis lazuli, known for its rich blue background with flecks of gold, was historically revered by royalty and scholars for its association with wisdom and truth.
In 1952, the Jewelry Industry Council of America added zircon to the December birthstone list. Zircon, especially in its blue variety, was valued for its brilliance and refractive fire, often described as a “rainbow in a stone.” This addition further diversified the December selection, offering a gemstone with both historical and geological significance.
The most recent addition came in 2002, when tanzanite was officially recognized as a December birthstone. Discovered in Tanzania in 1967, tanzanite is a relatively modern gemstone. Its deep blue and violet hues quickly captivated jewelers and collectors alike, and its rarity—being found only in the Merelani Hills of northern Tanzania—further elevated its status. Today, tanzanite is not only a December birthstone but also a traditional gift for the 24th wedding anniversary.
The inclusion of multiple December birthstones reflects a broader cultural shift toward personalization in jewelry. Rather than being limited to a single gemstone, individuals can now choose from a range of options that suit their personal preferences, budgets, and the symbolic meanings they wish to associate with their birthstone.
Geological Formation and Sources
Each of December’s birthstones has a distinct geological origin, formed under unique conditions that contribute to their appearance and value.
Zircon
Zircon is one of the oldest minerals on Earth, with some crystals dating back over 4 billion years. It forms in igneous rocks and is often found in metamorphic and sedimentary environments. The blue variety of zircon, which is most commonly associated with December, is produced through heat treatment. This treatment enhances its natural refractive properties and gives it the vibrant blue color that is highly sought after.
Zircon is mined in various parts of the world, including Australia, Thailand, Cambodia, and the United States. The blue zircon used in jewelry is typically heat-treated, a process that is both common and stable.
Topaz
Topaz is a silicate mineral that forms in pegmatites and high-temperature metamorphic rocks. It is known for its hardness (8 on the Mohs scale) and clarity. The blue topaz commonly associated with December is not naturally blue; it is usually colorless or pale yellow in its natural state and is treated to enhance its color.
Blue topaz is most commonly sourced from Brazil, but it is also found in Nigeria, the United States, and Madagascar. The color is achieved through irradiation and heat treatment, a process that is well-established in the gem industry.
Tanzanite
Tanzanite is a relatively rare gemstone, found exclusively in the Merelani Hills of northern Tanzania. It is a variety of the mineral zoisite and is known for its pleochroism, meaning it exhibits different colors under different lighting conditions. Tanzanite can appear blue, violet, or purplish depending on the viewing angle.
The gemstone was first discovered in 1967 by a Masai herdsman and was later identified as a new gem variety. Its short supply and striking color have made it a highly desirable gemstone in the jewelry market.
Lapis Lazuli
Lapis lazuli is a metamorphic rock composed primarily of lazurite, with varying amounts of other minerals such as pyrite, calcite, and diopside. Its deep blue color is due to the presence of lazurite, and the golden flecks of pyrite add a shimmering effect.
Lapis lazuli is most commonly sourced from Afghanistan, where it has been mined for thousands of years. It was highly prized in ancient Egypt and was used in jewelry, amulets, and even as pigment in cosmetics. Smaller deposits are found in Chile, Russia, and the United States.
Turquoise
Turquoise is a hydrated phosphate of aluminum and copper, and it forms in arid regions where the weathering of copper-rich rocks allows the mineral to develop. It is known for its distinctive blue-green color, which varies depending on the concentration of copper and the presence of iron.
Turquoise is mined in several countries, including the United States (particularly Nevada and Arizona), Iran, China, and Egypt. The most valuable turquoise is often found in the American Southwest, where it has been used in Native American jewelry for centuries.
Gemological Properties
Understanding the gemological properties of each December birthstone is essential for both jewelry buyers and gemologists. These properties determine the stone’s durability, appearance, and care requirements.
| Gemstone | Color | Hardness (Mohs Scale) | Refractive Index | Transparency | Luster | Common Cuts |
|---|---|---|---|---|---|---|
| Zircon | Blue, colorless, yellow, brown | 6.5–7.5 | 1.92–2.00 | Transparent to translucent | Vitreous | Round brilliant, cushion, oval |
| Topaz | Blue, colorless, yellow, pink | 8 | 1.61–1.63 | Transparent | Vitreous | Round brilliant, emerald, pear |
| Tanzanite | Blue, violet, purplish | 6–7 | 1.694–1.700 | Transparent to translucent | Vitreous | Cushion, oval, emerald |
| Lapis Lazuli | Deep blue with gold flecks | 5–6 | 1.62–1.64 | Opaque to translucent | Waxy to greasy | Cabochon |
| Turquoise | Blue-green | 5–6 | 1.61–1.65 | Opaque | Waxy | Cabochon, domed, freeform |
Zircon
Zircon is known for its high refractive index and dispersion, giving it a brilliance and fire that rivals diamond. The blue variety is especially popular for its vibrant color and clarity. However, zircon is relatively soft compared to other gemstones, with a hardness of 6.5–7.5 on the Mohs scale. This makes it susceptible to scratches and chipping if not handled carefully.
Topaz
Topaz is a very hard gemstone, with a Mohs hardness of 8, making it suitable for everyday wear. It is also known for its clarity and can be cut into a variety of styles. Blue topaz, in particular, is a popular choice for rings, pendants, and earrings due to its durability and affordability.
Tanzanite
Tanzanite has a hardness of 6–7 on the Mohs scale, making it suitable for use in jewelry, though it requires careful handling. Its pleochroism is one of its most distinguishing features, and it is often cut in a cushion or oval style to best showcase its color.
Lapis Lazuli
Lapis lazuli is a softer stone, with a hardness of 5–6 on the Mohs scale. It is opaque and is typically cut in a cabochon style to highlight its color and flecks of pyrite. Due to its softness, it is best suited for pendants, earrings, and brooches rather than rings.
Turquoise
Turquoise is also a relatively soft gemstone, with a hardness of 5–6 on the Mohs scale. It is opaque and is usually cut in a cabochon or domed style. Turquoise is known for its unique color and is often stabilized with resins to improve its durability and color consistency.
Symbolism and Metaphysical Beliefs
Each December birthstone carries its own set of symbolic and metaphysical associations, which have been passed down through history and continue to influence modern perceptions.
Zircon
Zircon is often associated with clarity, wisdom, and transformation. It is believed to enhance mental clarity and promote spiritual growth. Some cultures consider zircon to be a stone of prosperity and protection, especially in times of change.
Topaz
Topaz is traditionally believed to bring strength, courage, and good fortune. Blue topaz, in particular, is associated with calmness and serenity. In ancient times, topaz was believed to have the power to heal and protect against harm.
Tanzanite
Tanzanite is often linked to intuition, emotional healing, and spiritual awakening. Its deep blue color is thought to promote a sense of calm and balance. It is also associated with creativity and is believed to help open the heart and mind to new possibilities.
Lapis Lazuli
Lapis lazuli has long been associated with wisdom, truth, and enlightenment. In ancient Egypt, it was used in ceremonial masks and was believed to bring divine insight. It is also thought to enhance intellectual abilities and encourage a deeper understanding of the self and the universe.
Turquoise
Turquoise is one of the most culturally significant of December’s birthstones. It has been used for centuries as a protective talisman and is believed to bring good luck and positive energy. In Native American cultures, turquoise is considered a sacred stone that connects the physical and spiritual worlds. It is also associated with healing, communication, and emotional balance.
Care and Cleaning
Proper care is essential to maintaining the beauty and longevity of December’s birthstones. Due to their varying hardness and composition, different care methods are recommended for each gemstone.
Zircon
Zircon is relatively soft and can be scratched by harder gemstones or metals. It should be cleaned with a mild soap and warm water solution using a soft cloth or a soft-bristled brush. Avoid using steam or ultrasonic cleaners, as these can cause damage to the stone.
Topaz
Topaz is a durable gemstone that can be cleaned with warm, soapy water. It can also be cleaned using an ultrasonic cleaner. However, it should be kept away from extreme temperatures and harsh chemicals, as these can cause discoloration or damage.
Tanzanite
Tanzanite is relatively soft and sensitive to heat and light. It should be cleaned with a damp cloth and mild detergent. Avoid using steam or ultrasonic cleaners, as these can cause the stone to lose its color or become damaged.
Lapis Lazuli
Lapis lazuli is a soft and porous stone that should be handled with care. It can be cleaned with a soft cloth and mild soap and water. Avoid using abrasive materials or harsh chemicals, as these can scratch or discolor the stone.
Turquoise
Turquoise is a porous stone that can absorb oils and dirt. It should be cleaned with a soft cloth and mild soap. Avoid using ultrasonic or steam cleaners, as these can cause the stone to dry out or lose its color. It is also important to avoid exposing turquoise to strong chemicals or prolonged exposure to sunlight, as this can cause it to fade.
Conclusion
December’s birthstones offer a rich and diverse selection of gemstones that reflect the spirit of the season. From the brilliant fire of zircon to the deep blue hues of tanzanite and the ancient allure of turquoise and lapis lazuli, each stone carries its own unique history, symbolism, and beauty. Whether worn as a personal talisman or a piece of fine jewelry, these gemstones serve as a meaningful connection to the past and a celebration of individuality.
For those born in December, the choice of a birthstone is not merely an aesthetic decision but a personal one that resonates with their character and values. With their varied colors, histories, and meanings, December’s birthstones continue to inspire and captivate, making them a fitting symbol for the end of the year and the promise of new beginnings.