December is a month of contrasts and transitions—of cold winds and warm holiday cheer, of anticipation and celebration. It is also a month rich in gemological significance, as it is home to not one, but three official birthstones: turquoise, tanzanite, and zircon. These stones, each with its own unique color, history, and symbolism, offer a fascinating journey through time, culture, and geology. Whether you were born in December or simply drawn to the allure of these gems, understanding their origins, properties, and meanings can deepen your appreciation for these natural treasures.
This article explores the three December birthstones in depth, drawing from authoritative gemological and historical sources to present an accurate and comprehensive overview. We will examine the historical significance, geological properties, cultural symbolism, and modern uses of each stone, providing a detailed guide for gemstone enthusiasts, collectors, and those curious about the birthstones associated with the final month of the year.
History and Lore of the December Birthstones
Turquoise: An Ancient Symbol of Protection and Prosperity
Among the three December birthstones, turquoise is perhaps the most historically significant. Its use dates back thousands of years, with evidence of its presence in ancient Egyptian tombs, including the famed funerary mask of Pharaoh Tutankhamun. This deep blue-green gem was believed to bring health, good fortune, and protection to its wearer.
In ancient Egypt, turquoise was considered a sacred stone and was often used in jewelry and amulets to ward off evil. The Egyptians believed that turquoise came from the bones of birds that died in the sky and that the gods themselves wore it. This belief was echoed in ancient Persia, where turquoise was revered as a "sky stone" and associated with divine protection.
Turquoise also played a significant role in Native American cultures, particularly among the Apache, Pueblo, and Hopi tribes. The Apache believed that following a rainbow to its end would lead to turquoise, and that attaching the stone to a bow or weapon could improve one's aim. The Pueblo people saw turquoise as a gift from the sky, while the Hopi believed it was formed by lizards scurrying over the earth.
By the 13th century, European cultures had adopted turquoise as a symbol of protection from falls and accidents, especially for those who rode horses. It was said that the gem would break into pieces if disaster was imminent, acting as a natural warning. In Victorian England, turquoise became a fashionable accessory, often used in rings and brooches to convey "forget me not" sentiments.
Today, turquoise is celebrated as the birthstone for December and also marks the 11th wedding anniversary. In Tibet, it is considered a national treasure, believed to bring health, good fortune, and spiritual protection.
Tanzanite: A Modern Marvel from Tanzania
In contrast to the ancient lineage of turquoise, tanzanite is a relatively newcomer to the gemstone world. Discovered in 1967 in the Merelani Hills of northern Tanzania, it was initially identified as a type of zoisite. The gem was later treated with heat to enhance its color and officially named tanzanite in honor of its country of origin.
The stone was quickly marketed by Tiffany & Co., who recognized its "velvety" blue and violet hues and launched a major advertising campaign in 1968. This helped tanzanite gain international recognition and popularity. It is now not only a December birthstone but also a symbol of the 24th wedding anniversary.
Tanzanite’s unique color range—from deep blue to rich violet—has made it a favorite among jewelers and collectors. Its rarity also adds to its allure: it is only found in Tanzania, and it is estimated to have a limited lifespan of about 500 years before the mines are depleted.
The gemstone’s discovery and rapid rise in popularity reflect a modern era of gem exploration and marketing, where scientific advancements and strategic branding play as much a role as natural beauty.
Zircon: A Timeless Stone with a Shimmering Past
Zircon, the third December birthstone, has a long and varied history. Known in the Victorian era for its bright blue color, it was a popular choice in English estate jewelry from the 1880s. Zircon is one of the oldest minerals on Earth, with some crystals dating back over 4 billion years, making it a true geological relic.
The stone is often heat-treated to enhance its color, producing a range from colorless and blue to orange, yellow, and red. These treatments make zircon a versatile gem that can mimic the appearance of other precious stones like diamonds, sapphires, and rubies.
Zircon is found in several parts of the world, including Sri Lanka, Australia, Myanmar, Vietnam, and Cambodia. In Sri Lanka, the gem is often found in alluvial deposits, where it has been worn smooth by rivers over thousands of years. In Australia, the Zircon Hill in the Harts Range is a notable source of yellow-brown, orangy brown, pink, and purple zircon.
Zircon has also been used in astronomical and geological dating due to its ability to preserve radioactive elements over long periods. This makes it a valuable tool for scientists, in addition to its beauty and historical significance in jewelry.
Geological Formation and Sources
Turquoise: A Mineral of Earth and Sky
Turquoise is a phosphate mineral, with the chemical formula CuAl6(PO4)4(OH)8·4H2O. It is typically found in arid regions, where it forms through the oxidation of copper deposits by phosphoric acid, which is carried by rainwater and groundwater. The matrix—the host rock in which turquoise forms—often contains black or brown veins, giving the gem its distinctive appearance.
Iran has been a major source of turquoise for over a thousand years, particularly in the Nishapur district, where it is known for producing the highly prized "Persian blue". Other notable sources include the American Southwest, where Native American tribes have mined the stone for centuries, and China, where it has been used in jade-like carvings and inlays.
Turquoise is not a naturally clear gemstone; it is semi-translucent to opaque, and its color can vary widely depending on the concentration of copper and aluminum, as well as the presence of impurities like iron and other metals. This variation in color and texture is one of the reasons why turquoise is so visually appealing and highly collectible.
Tanzanite: A Unique Geological Phenomenon
Tanzanite is a trigonal mineral, a variety of cymophane (a type of zoisite), with the chemical formula Ca2Al3(SiO4)(Si2O7)O(OH). It is only found in one place on Earth: the Merelani Hills of northern Tanzania, where it is mined from a deposit that sits under a layer of grass and scrubland. The region is also close to Mount Kilimanjaro, whose snow-capped peaks contrast with the rocky soil and scrub brush of the mining area.
The blue and violet colors of tanzanite are due to the presence of vanadium and the way light interacts with the crystal structure. However, the gem is not naturally blue; it is typically found in a brownish or yellowish hue, and it is heat-treated to bring out its signature blue color. This treatment is stable in most cases, though some stones may revert to their original color if exposed to prolonged sunlight or high temperatures.
Tanzanite’s rarity is due to both the limited geographic location and the short lifespan of the mine. Geologists estimate that the deposit may be exhausted within the next few decades, which has led to increased demand and value for high-quality tanzanite stones.
Zircon: A Mineral of Time and Transformation
Zircon is a zirconium silicate mineral, with the chemical formula ZrSiO4. It is one of the oldest minerals on Earth, with some zircon crystals found in Australia that are over 4 billion years old. This makes zircon a geological time capsule, often used by scientists to date the age of the Earth and ancient rocks.
Zircon is typically colorless or yellow, but it can be heat-treated to produce blue, red, or green varieties. These treatments are stable in most cases, though some zircons may fade if exposed to intense light or heat. Zircon is also resistant to chemical weathering, which is why it is often found in alluvial deposits, where it has been worn down by rivers and streams over time.
The most notable sources of zircon include:
- Sri Lanka: Known for producing high-quality blue and colorless zircon, often found in alluvial deposits.
- Australia: The Harts Range in central Australia is a major source of yellow-brown and pink zircon.
- Myanmar, Vietnam, and Cambodia: These countries also produce zircon, often in orange and red varieties.
Zircon is rated between 6 and 7.5 on the Mohs scale of hardness, which means it is relatively durable but can still be damaged if exposed to abrasion or impact. It is also stable in most environments, though some heat-treated stones may change color over time.
Gemological Properties
| Gemstone | Color | Hardness (Mohs) | Chemical Formula | Transparency | Sources |
|---|---|---|---|---|---|
| Turquoise | Blue, green, greenish-yellow | 5–6 | CuAl6(PO4)4(OH)8·4H2O | Opaque to semi-translucent | Iran, N. America, China |
| Tanzanite | Blue, violet | 6–7 | Ca2Al3(SiO4)(Si2O7)O(OH) | Transparent to translucent | Tanzania |
| Zircon | Blue, colorless, red, yellow, orange | 6–7.5 | ZrSiO4 | Transparent to translucent | Sri Lanka, Australia, Myanmar, Vietnam, Cambodia |
Each of these gemstones possesses unique physical and optical properties that make them valuable in both jewelry and scientific contexts.
Turquoise
- Color: Ranges from deep blue to green and greenish-yellow, with black or brown matrix veins.
- Hardness: 5–6 on the Mohs scale, making it relatively soft and prone to scratching.
- Transparency: Opaque to semi-translucent.
- Luster: Waxy or dull to glassy, depending on the surface treatment.
- Refractive Index: 1.60–1.65.
- Special Properties: Often polished and stabilized to improve durability and color.
Tanzanite
- Color: Blue to violet, with the blue variety being the most valuable.
- Hardness: 6–7 on the Mohs scale, making it relatively durable.
- Transparency: Transparent to translucent.
- Luster: Glassy to vitreous.
- Refractive Index: 1.69–1.70.
- Special Properties: Often heat-treated to enhance color, and it is one of the few gemstones that exhibit pleochroism—displaying different colors when viewed from different angles.
Zircon
- Color: Blue, colorless, red, yellow, orange.
- Hardness: 6–7.5 on the Mohs scale, making it more durable than turquoise.
- Transparency: Transparent to translucent.
- Luster: Glassy to vitreous.
- Refractive Index: 1.92–2.01.
- Special Properties: Known for its high refractive index, which gives it a sparkling appearance. It is often heat-treated to enhance color and is used in jewelry as a diamond simulant.
Symbolism and Metaphysical Beliefs
Turquoise: A Stone of Protection and Positive Energy
Turquoise has long been associated with protection, good health, and positive energy. In ancient Egypt, it was believed to ward off evil and bring good fortune to the wearer. The Pharaohs and other rulers adorned themselves with turquoise as a sign of divine favor and protection.
In Native American cultures, turquoise was seen as a stone of healing and harmony. The Apache believed that following a rainbow to its end would lead to turquoise, and that it could improve one’s aim when attached to a bow or weapon. The Hopi believed it was formed by lizards scurrying over the earth, while the Pueblo saw it as a gift from the sky.
In Hindu tradition, it was believed that seeing turquoise after observing a new moon would bring wealth and prosperity. In Victorian England, turquoise rings were often given as symbols of love and remembrance, with the phrase "forget me not" associated with the gem.
In modern times, turquoise is still used in jewelry and spiritual practices, often as a stone of peace, protection, and positive energy. It is also considered a stone of communication, helping to open the throat chakra and encourage honest expression.
Tanzanite: A Stone of Transformation and Emotion
Tanzanite is a relatively new gemstone, but it has already gained a strong following in both the gemological and spiritual communities. It is often associated with emotional healing, transformation, and intuition.
In spiritual circles, tanzanite is believed to open the heart and throat chakras, promoting emotional balance and self-expression. It is also thought to enhance intuition and spiritual awareness, making it a popular stone for meditation and healing practices.
In jewelry, tanzanite is valued for its rich, velvety colors and elegant appearance. It is often used in designer rings, pendants, and earrings, and it is particularly popular for December birthdays.
Zircon: A Stone of Clarity and Light
Zircon is often associated with clarity, light, and spiritual transformation. In Victorian times, it was used in jewelry to symbolize love and devotion, and it was particularly popular in estate pieces from the 1880s.
In spiritual traditions, zircon is believed to enhance mental clarity and intuition, and it is often used in meditation and healing practices. It is also thought to protect against negative energy and promote positive change.
Zircon is one of the oldest minerals on Earth, and it is often used in geological and astronomical dating due to its ability to preserve radioactive elements over long periods. This makes it not only a beautiful gemstone but also a valuable scientific tool.
Care and Cleaning of December Birthstones
Proper care and cleaning are essential for preserving the beauty and value of December birthstones. While each stone has its own unique properties and vulnerabilities, there are general guidelines that apply to all of them.
Turquoise
- Hardness: 5–6 on the Mohs scale, making it relatively soft.
- Cleaning: Clean with a soft brush, mild soap, and warm water. Ultrasonic and steam cleaners are not recommended, as they can damage the stone or its matrix.
- Storage: Store turquoise in a soft cloth or padded jewelry box to avoid scratches.
- Avoid: Exposure to heat, sunlight, and chemicals, as these can alter the color and stability of the stone.
Tanzanite
- Hardness: 6–7 on the Mohs scale, making it moderately durable.
- Cleaning: Clean with a soft brush, mild soap, and warm water. Ultrasonic and steam cleaners are generally safe, but check with the jeweler to be sure.
- Storage: Store tanzanite in a separate compartment to avoid scratches.
- Avoid: Prolonged exposure to sunlight or heat, as this can cause the color to fade in some stones.
Zircon
- Hardness: 6–7.5 on the Mohs scale, making it relatively durable.
- Cleaning: Clean with a soft brush, mild soap, and warm water. Ultrasonic and steam cleaners are not recommended, as they can damage heat-treated stones.
- Storage: Store zircon in a soft cloth or padded box to prevent scratches.
- Avoid: Rough use or abrasion, as zircon can chip or abrade over time.
Conclusion
The December birthstones—turquoise, tanzanite, and zircon—offer a fascinating blend of historical significance, geological rarity, and cultural symbolism. From the ancient Egyptian tombs to the modern jewelry displays in high-end boutiques, these stones continue to captivate and inspire those who wear them.
Whether you are drawn to the deep blue of turquoise, the velvety richness of tanzanite, or the sparkling brilliance of zircon, each of these December birthstones has a unique story to tell. Understanding their origins, properties, and meanings can deepen your appreciation and help you make an informed choice when selecting a December birthstone for yourself or a loved one.
As the final month of the year, December is a time of reflection, celebration, and new beginnings. Choosing a December birthstone can be a beautiful way to honor both the past and the future, and to carry with you a piece of history, beauty, and meaning throughout the year.