December stands uniquely adorned in the gemological calendar, being the sole month officially associated with four distinct birthstones: turquoise, zircon, tanzanite, and blue topaz. This abundance presents a fascinating narrative of historical evolution, cultural adaptation, and modern gemological preference. While most months are linked to a single gem, December’s quartet offers a spectrum of colors and properties, from the ancient, opaque blues of turquoise to the brilliant, fiery sparkle of zircon and the vivid violet-blue of tanzanite. The journey to this multiplicity is a story that spans millennia, tracing back to ancient traditions, navigating through standardization efforts, and arriving at contemporary choices driven by both aesthetic appeal and practical durability. This article delves into the history, geology, properties, and symbolism of each of December’s four birthstones, providing a comprehensive guide for enthusiasts, collectors, and anyone born in the month of celebration and reflection.
The Historical Evolution of December's Birthstones
The tradition of associating gemstones with specific months of the year has ancient roots, with one of the earliest recorded references found in the Biblical Book of Exodus, which describes the High Priest’s Breastplate adorned with twelve gemstones representing the tribes of Israel. Over centuries, various cultures developed their own lists, influenced by local gem availability, mythology, and spiritual beliefs. For December, the earliest and most enduring association is with turquoise.
Turquoise has been linked to December since long before any modern standardization, with its connection dating back at least to the 1300s in ancient Persia, Egypt, and other Middle Eastern cultures. These societies valued turquoise not only for its beauty but also for its perceived protective and healing properties. The cool blue shade of the gem was believed to resemble the clear skies of winter, making it a natural symbolic choice for the final month of the year.
The modern era of birthstone standardization began in 1912 when the Jewelers of America (JA) created an official list. This initial list recognized only two stones for December: turquoise and lapis lazuli. Turquoise was the primary stone, while lapis lazuli served as a less common alternative. However, the list was not static and underwent revisions over time, reflecting changes in gemstone availability, popularity, and market trends.
The first significant addition to December’s birthstones was zircon. Although zircon is an ancient gemstone, its popularity surged in the early 20th century due to its brilliant sparkle and the appeal of its blue hues. Zircon’s properties made it a compelling alternative to the then-listed lapis lazuli, offering greater durability and a more brilliant appearance. Consequently, zircon was formally promoted from an alternative to a primary December birthstone, replacing lapis lazuli in the official list.
The next major evolution occurred with the introduction of tanzanite. This rare blue-violet mineral was first discovered in the 1960s in Tanzania (hence its name) and quickly gained popularity in jewelry. Its vivid color, often described as echoing December’s clear winter nights, and its relatively recent discovery made it a symbolic representation of December’s transitional place between the old year and the new. After decades of prominence in the market, the Gemological Institute of America (GIA) officially recognized tanzanite as a December birthstone in 2002.
The fourth stone, blue topaz, was added to the list by the American Gem Trade Association (AGTA) in 2002. While natural blue topaz is exceptionally rare, the gemstone has become widely available through modern treatment processes that enhance its color. Its addition was driven by its accessibility, affordability, and serene ice-blue hue, which resonates with the winter month. Thus, by the early 21st century, December had become uniquely distinguished as the month with four official birthstones.
Turquoise: The Ancient Protector
Turquoise, the original December birthstone, is a semi-translucent to opaque gem that ranges from blue to green, often featuring veins of matrix—the remnants of the host rock in which it formed. This distinctive appearance, sometimes in a spectacular spiderweb pattern, is a hallmark of the stone. It has been cherished for millennia, adorning the pharaohs of ancient Egypt and being carved by Chinese artisans over 3,000 years ago.
Geological Formation and Sources: Turquoise forms in arid regions of the world, primarily in areas with copper-rich geological formations and specific weather conditions that facilitate its development. Significant sources include the southwestern United States (particularly Arizona and New Mexico), Iran, Egypt, China, Mexico, and parts of Central Asia and Africa. The stone’s formation requires a combination of water, aluminum, and copper, with the color ranging from sky blue to green depending on the amount of iron and other trace elements present.
Gemological Properties: Turquoise is known for its relatively low hardness, rating around 5 to 6 on the Mohs scale. This makes it a softer gemstone that requires careful handling to avoid scratches and damage. Its composition is a hydrated phosphate of copper and aluminum, contributing to its distinctive color and opacity.
Symbolism and Metaphysical Beliefs: Throughout history, turquoise has been imbued with powerful symbolic meanings. It was believed to possess many beneficial powers, such as guaranteeing health and good fortune. From the 13th century onward, it was thought to protect the wearer from falling (especially off horses) and would break into several pieces at the approach of disaster. Hindu mystics maintained that seeing a turquoise after beholding the new moon ensured fantastic wealth. Among Native Americans, the Apache believed turquoise could be found by following a rainbow to its end. In modern metaphysical beliefs, turquoise is said to stimulate wisdom, trust, and understanding, strengthen the immune system, aid in nutrient absorption, regulate bodily fluids, and provide protection and bring good fortune.
Care and Cleaning: Due to its moderate hardness and potential porosity, turquoise requires gentle care. It should be cleaned with a soft, damp cloth and mild soap, avoiding harsh chemicals, ultrasonic cleaners, and prolonged exposure to water, heat, or direct sunlight, which can cause discoloration or cracking. Jewelry set with turquoise should be stored separately to prevent scratching by harder gems.
Zircon: The Fire of the Skies
Zircon, not to be confused with cubic zirconia, is one of the oldest minerals on Earth, with crystals found in Australia dating back over 4.4 billion years. While it occurs in a variety of colors, the blue variety is most associated with December. Its brilliant sparkle, often compared to that of a diamond, and its compelling blue hues made it a popular choice in the early 20th century.
Geological Formation and Sources: Zircon forms in igneous and metamorphic rocks. Major sources of gem-quality zircon include Sri Lanka, Cambodia, Myanmar, and Australia. The blue color in zircon is typically achieved through heat treatment of brownish crystals, a process that also enhances its brilliance.
Gemological Properties: Zircon is a harder and more durable gemstone than turquoise, with a Mohs hardness of 6.5 to 7.5. It has a high refractive index and strong dispersion, giving it exceptional fire and brilliance. Its chemical formula is ZrSiO₄ (zirconium silicate). Blue zircon, in particular, is prized for its vivid, often electric blue color.
Symbolism and Metaphysical Beliefs: Zircon is associated with honor, self-esteem, and clarity. Metaphysically, it is believed to relieve pain and inflammation, protect against nightmares and evil spirits, and bring prosperity and draw love. Its historical use in jewelry and its enduring sparkle have made it a symbol of wisdom and clarity.
Care and Cleaning: With its higher hardness, zircon is relatively durable but can be brittle and prone to chipping due to its perfect cleavage in two directions. It should be protected from sharp blows and extreme temperature changes. Cleaning can be done with warm, soapy water and a soft brush; ultrasonic and steam cleaners are generally safe for untreated zircon but should be avoided for stones that have been fracture-filled.
Tanzanite: The Modern Marvel
Tanzanite is a relative newcomer to the gem world, first discovered in the 1960s in the Merelani Hills of Tanzania. Its discovery was a significant event, as it is found in only one location on Earth. The gemstone’s vivid blue-violet color, ranging from ultramarine to lavender, is unique and highly sought after. It was officially recognized as a December birthstone in 2002 by the GIA.
Geological Formation and Sources: Tanzanite forms under specific geological conditions found only in a small area of Tanzania. Its formation is linked to the metamorphism of limestone and the presence of vanadium, which gives the stone its characteristic color. The mining area is extremely limited, contributing to its rarity and value.
Gemological Properties: Tanzanite has a Mohs hardness of 6.5 to 7, making it suitable for jewelry but requiring some care. It is a variety of the mineral zoisite and is typically treated with heat to enhance its blue color, a standard practice in the industry. Its trichroic nature allows it to show three different colors—blue, violet, and burgundy—from different crystal directions.
Symbolism and Metaphysical Beliefs: Tanzanite is associated with intuition, psychic abilities, spiritual growth, and inner peace. It is believed to balance the energies of the mind, body, and spirit and to foster compassion, gentleness, and empathy. Its recent discovery and unique color have made it a symbol of modernity and transformation.
Care and Cleaning: Tanzanite should be cleaned with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaning, as these can cause damage. Due to its cleavage, it should be protected from knocks and extreme temperature changes. It is best stored in a soft cloth or padded box.
Blue Topaz: The Serene Ice
Blue topaz, while naturally occurring in very pale blue shades, is most commonly found in the market as a treated stone. The deep, vivid blue hues are achieved through irradiation and heat treatment of colorless or pale blue topaz. It was added to the December birthstone list in 2002 by the AGTA, offering an affordable and accessible option.
Geological Formation and Sources: Topaz is a silicate mineral that forms in pegmatites and hydrothermal veins. Natural blue topaz is extremely rare; the majority of commercial blue topaz is treated. Major sources of topaz include Brazil, Sri Lanka, and Nigeria.
Gemological Properties: Blue topaz has a Mohs hardness of 8, making it one of the harder gemstones and very durable for jewelry. Its chemical formula is Al₂SiO₄(F,OH)₂ (aluminum silicate fluoride hydroxide). The treated blue topaz comes in various shades, from sky blue ("London Blue") to a deeper, more saturated blue ("Swiss Blue").
Symbolism and Metaphysical Beliefs: Blue topaz is associated with calm, clarity, and communication. It is believed to promote truth, forgiveness, and emotional balance. Metaphysically, it is thought to aid in meditation, reduce stress, and enhance psychic abilities. Its cool blue color is linked to tranquility and peace.
Care and Cleaning: With its high hardness, blue topaz is quite durable and resistant to scratching. It can be cleaned with warm, soapy water and a soft brush. Ultrasonic cleaners are generally safe, but steam cleaning should be avoided if the stone has been fracture-filled. It is stable under normal conditions but should be protected from extreme heat.
Comparative Overview of December's Birthstones
The four December birthstones offer a diverse range of properties, making them suitable for different preferences and uses. The following table summarizes key gemological and symbolic aspects based on the provided sources.
| Gemstone | Mohs Hardness | Primary Color | Key Symbolism | Notable Sources | Care Considerations |
|---|---|---|---|---|---|
| Turquoise | 5 - 6 | Blue to Green, often with matrix | Protection, wisdom, good fortune | Southwestern USA, Iran, Egypt, China, Mexico | Gentle cleaning; avoid chemicals, heat, and prolonged water exposure |
| Zircon | 6.5 - 7.5 | Blue (often treated), also colorless, yellow, brown | Honor, self-esteem, clarity, prosperity | Sri Lanka, Cambodia, Myanmar, Australia | Avoid sharp blows; can be brittle; safe for ultrasonic (if untreated) |
| Tanzanite | 6.5 - 7 | Blue-violet (trichroic: blue, violet, burgundy) | Intuition, spiritual growth, inner peace | Tanzania (only source) | Avoid ultrasonic/steam; gentle cleaning; protect from knocks |
| Blue Topaz | 8 | Sky blue to deep blue (treated) | Calm, clarity, communication, truth | Brazil, Sri Lanka, Nigeria (treated globally) | Durable; avoid extreme heat; safe for ultrasonic (if untreated) |
Care and Maintenance for December Birthstones
Proper care is essential to preserve the beauty and longevity of any gemstone jewelry. Given the varying hardness and durability of December’s birthstones, specific guidelines should be followed.
For turquoise, its softness and porosity make it the most delicate. It should be wiped clean with a soft, damp cloth. Avoid submerging it in water, as it can absorb liquids and change color. Harsh chemicals, including household cleaners, perfumes, and lotions, can damage its surface. Store turquoise jewelry separately in a soft pouch to prevent scratching.
Zircon is harder but can be brittle. It is important to protect it from sharp impacts that could cause chipping. While it can generally withstand ultrasonic cleaning, it is advisable to check if the stone has been treated or fracture-filled. Sudden temperature changes should be avoided.
Tanzanite requires careful handling due to its perfect cleavage. It should never be subjected to ultrasonic or steam cleaning, as vibrations and heat can cause internal fractures. Cleaning with warm, soapy water and a soft brush is recommended. Store it in a padded compartment away from other jewelry.
Blue topaz is the most durable of the four, thanks to its high hardness. It can be cleaned with a soft brush and soapy water, and ultrasonic cleaning is typically safe for untreated stones. However, avoid exposing it to extreme heat, which could affect any treatments or cause damage to fracture-filled stones.
Conclusion
December’s status as the month with four birthstones is a testament to the dynamic nature of gemological traditions. From the ancient, protective turquoise to the fiery brilliance of zircon, the modern allure of tanzanite, and the serene accessibility of blue topaz, each stone carries a unique history, set of properties, and symbolic meaning. This quartet offers a remarkable diversity, allowing individuals born in December to choose a gemstone that resonates with their personal style, budget, and spiritual inclinations. The evolution of December’s birthstones—from a single ancient stone to a modern quartet—reflects both the enduring human connection to gemstones and the ever-changing landscape of the global gem trade. Whether chosen for its historical significance, geological rarity, or metaphysical properties, each of these four gems provides a meaningful and beautiful link to the month of celebration and reflection.