December, the final month of the year, is marked not only by the winter season and holiday celebrations but also by the rich tradition of birthstones. Unlike months with a single birthstone, December is uniquely associated with multiple gemstones—each carrying its own history, symbolism, and gemological significance. The modern list includes blue zircon, tanzanite, and blue topaz, while the traditional December birthstones are lapis lazuli and turquoise. These gems, with their diverse shades of blue and their deep cultural roots, make December a particularly fascinating month in the world of birthstones.
This article delves into the history, geological properties, symbolic meanings, and practical care of December’s birthstones. We will explore how these gems have been cherished across centuries, their role in jewelry and spirituality, and the reasons they remain popular today. Whether you are a gemstone enthusiast, a jewelry buyer, or simply curious about the significance of these beautiful stones, this guide offers a comprehensive look at December’s birthstones.
History and Lore
The practice of associating gemstones with specific months dates back to ancient times. One of the earliest references comes from the Biblical Breastplate of Aaron, mentioned in the Book of Exodus, which lists 12 stones believed to represent the 12 tribes of Israel. While the identities of these stones remain debated, the concept of linking gemstones to months and zodiac signs gradually evolved over centuries.
In the 14th century, the Jewish Kabbalah and medieval European traditions helped formalize the modern birthstone list. By the 19th century, jewelers and gemologists had standardized these associations, and by the mid-20th century, the National Association of Jewelers (now the Jewelers of America) officially recognized December's birthstones.
Evolution of December's Birthstones
December’s birthstone list has undergone notable changes over time:
- 1870: The earliest documented version listed turquoise as the sole December birthstone, as per Tiffany & Co.’s “Gregorian Birthstone Poems” pamphlet.
- 1912: Lapis lazuli was added as an alternative gemstone by the National Association of Jewelers.
- 1952: Zircon, especially the blue variety, was introduced to the list by the Jewelry Industry Council of America.
- 2002: Tanzanite, a relatively new gemstone discovered in Tanzania in the 1960s, was added to the modern December list.
This evolution reflects not only the growing appreciation for gemstones with similar properties to diamonds but also the changing tastes and preferences in jewelry design over the decades.
Cultural Significance
December’s gemstones have been revered for their symbolic meanings and spiritual associations. Lapis lazuli, for instance, was highly prized by ancient Egyptians, who used it to adorn pharaohs and create ceremonial objects. It was considered a stone of truth and wisdom, often associated with royalty and divine insight.
Turquoise, on the other hand, has been cherished by numerous cultures, including the ancient Egyptians, Chinese, and Native American tribes. The Chinese carved it into jade-like ornaments over 3,000 years ago, while Native Americans used it in ceremonial jewelry and as a protective amulet. In many cultures, turquoise is believed to bring good fortune, promote healing, and protect the wearer from harm.
Tanzanite, though the youngest of December’s birthstones, has quickly gained popularity due to its vivid blue to violet hues and its limited availability. Discovered in 1967 in Tanzania, it was marketed as a “modern” alternative to traditional gems, yet it carries the same spiritual resonance of protection and transformation.
Geological Formation and Sources
Understanding the geological formation and natural sources of a gemstone provides insight into its rarity, value, and physical properties. December’s birthstones are no exception, each forming under unique conditions and found in specific geographic regions.
Blue Zircon
Zircon is a mineral that occurs in various colors, but blue zircon, also known as tanzanite-like zircon, is particularly popular as a birthstone. It is formed when natural zircon is heat-treated to enhance its color. Zircon is found in igneous rocks and is often mined from alluvial deposits. Major sources include Brazil, Cambodia, and Thailand.
Tanzanite
Tanzanite is a variety of the mineral columbite-zircon, known for its intense blue to violet hues. It was discovered in 1967 in the Merelani Hills near Arusha, Tanzania, from which it gets its name. Tanzanite forms under high-pressure metamorphic conditions and is only found in this specific region, making it one of the rarest gemstones in the world.
Blue Topaz
Topaz is a silicate mineral with a hexagonal crystal structure. Blue topaz, which is typically colorless in its natural state, is treated with irradiation and heat to produce its beautiful blue color. The most common sources of blue topaz are Brazil, Mexico, and Nigeria. Brazil is particularly known for its large deposits of topaz.
Lapis Lazuli
Lapis lazuli is a metamorphic rock composed primarily of lazurite, along with other minerals like pyrite and calcite. It forms under high-pressure, low-temperature conditions and is typically found in mountainous regions. The most famous source of lapis lazuli is Afghanistan, where it has been mined for thousands of years. Other notable sources include Russia, Canada, and the United States.
Turquoise
Turquoise is a hydrated phosphate of aluminum and copper, forming in the oxidized zone of copper deposits. It is commonly found in desert environments and is often associated with limestone. Major sources of turquoise include Iran, China, the United States, and Mexico. The American Southwest, particularly Arizona and Nevada, is known for producing high-quality turquoise used in Native American jewelry.
Gemological Properties
Each of December's birthstones has distinct gemological properties that influence their appearance, durability, and suitability for jewelry. Below is a detailed overview of their physical and optical characteristics.
Blue Zircon
- Color: Blue (often treated to enhance color)
- Hardness: 6–7.5 on the Mohs scale
- Refractive Index: 1.81–2.00
- Specific Gravity: 3.9–4.7
- Chemical Formula: ZrSiO₄
- Luster: Vitreous to resinous
- Transparency: Transparent to translucent
Blue zircon is known for its high refractive index, which gives it a brilliant, glassy luster. Its relatively high dispersion (ability to refract light) makes it resemble diamonds, especially in certain cuts.
Tanzanite
- Color: Blue to violet (color changes under different lighting)
- Hardness: 6–7 on the Mohs scale
- Refractive Index: 1.694–1.706
- Specific Gravity: 3.3–3.4
- Chemical Formula: CaAl₂(AlSiO₄)(OH)₂
- Luster: Vitreous
- Transparency: Transparent
Tanzanite is a pleochroic gemstone, meaning it displays different colors when viewed from different angles. It is also sensitive to heat and light, which can alter its color.
Blue Topaz
- Color: Blue (naturally colorless; blue achieved via irradiation and heat)
- Hardness: 8 on the Mohs scale
- Refractive Index: 1.61–1.63
- Specific Gravity: 3.4–3.6
- Chemical Formula: Al₂SiO₄(F,OH)₂
- Luster: Vitreous
- Transparency: Transparent
Blue topaz is durable and has a relatively high hardness, making it suitable for everyday jewelry. Its clarity and brilliance make it a popular alternative to diamonds.
Lapis Lazuli
- Color: Deep blue with golden pyrite flecks
- Hardness: 5–6 on the Mohs scale
- Refractive Index: 1.5–1.7
- Specific Gravity: 2.4–2.9
- Chemical Composition: Lazurite, calcite, and pyrite
- Luster: Waxy to greasy
- Transparency: Opaque to translucent
Lapis lazuli is an opaque gemstone used mainly for cabochons and ornamental objects. It is often carved or inlaid in mosaics and is not typically faceted.
Turquoise
- Color: Blue to green
- Hardness: 5–6 on the Mohs scale
- Refractive Index: 1.61–1.65
- Specific Gravity: 2.6–2.8
- Chemical Formula: CuAl₆(PO₄)₄(OH)₈·4H₂O
- Luster: Waxy to sub-vitreous
- Transparency: Translucent to opaque
Turquoise is a relatively soft gemstone that can be easily scratched or damaged. It is often stabilized with resins to improve its durability.
Symbolism and Metaphysical Beliefs
Throughout history, gemstones have been believed to hold mystical properties and energies. December’s birthstones are no exception, each carrying its own set of symbolic meanings and metaphysical associations.
Blue Zircon
Blue zircon has long been associated with wisdom, intuition, and spiritual awakening. In medieval Europe, it was believed to enhance dream recall and promote mental clarity. Some sources suggest that zircon was used in divination and was worn by scholars and philosophers to stimulate intellectual growth.
Tanzanite
Tanzanite is considered a stone of transformation and emotional healing. It is believed to help the wearer release old patterns, fears, and emotional blockages. In some metaphysical traditions, it is associated with the third eye and crown chakras, enhancing spiritual insight and connection to higher consciousness.
Blue Topaz
Blue topaz is often linked to calmness, serenity, and emotional balance. It is believed to help reduce stress and promote a sense of inner peace. In some cultures, blue topaz is associated with communication and truth, making it a popular stone for those seeking to express themselves more clearly and honestly.
Lapis Lazuli
Lapis lazuli has been revered for its intellectual and spiritual properties. It was used by ancient Egyptians as a stone of truth and was believed to enhance wisdom, intuition, and eloquence. In modern metaphysical practices, it is associated with the throat chakra, aiding in communication and self-expression.
Turquoise
Turquoise is one of the most powerful protective stones in the world. It has been used for centuries as a talisman of good fortune and protection. In Native American traditions, turquoise is considered the "stone of the sky" and is often used in ceremonial jewelry and amulets. It is believed to promote healing, enhance creativity, and protect the wearer from negative energies.
Care and Cleaning
Due to their varying hardness and sensitivity to environmental factors, the care and cleaning of December’s birthstones require special attention. Proper care ensures that these gemstones retain their beauty and durability over time.
Blue Zircon
- Cleaning: Use a soft cloth and mild soap with warm water. Avoid steam and ultrasonic cleaners, as zircon can be damaged by excessive heat or vibration.
- Storage: Store in a separate compartment to prevent scratching from harder stones.
Tanzanite
- Cleaning: Clean with a soft brush and warm soapy water. Avoid exposing to direct sunlight for long periods, as this can cause color fading.
- Storage: Keep in a cool, dark place to preserve its color.
Blue Topaz
- Cleaning: Can be cleaned with a soft cloth and mild soap or in an ultrasonic cleaner.
- Storage: Safe to store with other gemstones due to its high hardness.
Lapis Lazuli
- Cleaning: Wipe with a soft cloth and mild soap. Avoid using harsh chemicals or ultrasonic cleaners.
- Storage: Store in a soft cloth or separate compartment to prevent scratches.
Turquoise
- Cleaning: Use a soft cloth with mild soap and water. Avoid exposure to strong chemicals and excessive heat.
- Storage: Store in a cool, dry place. If stabilized, avoid soaking in water for long periods.
Conclusion
December’s birthstones—blue zircon, tanzanite, blue topaz, lapis lazuli, and turquoise—represent a fascinating blend of natural beauty, historical significance, and spiritual meaning. From the regal blue of lapis lazuli to the vibrant hues of turquoise and the modern allure of tanzanite, each gemstone offers a unique expression of the month’s essence.
These gemstones have been cherished for centuries, not only for their aesthetic appeal but also for their symbolic and metaphysical properties. Whether used in jewelry, spiritual practices, or decorative arts, December’s birthstones continue to captivate and inspire.
For those born in December, these gems serve as a personal connection to history, culture, and the natural world. Choosing a December birthstone can be a meaningful way to express individuality, celebrate heritage, and embrace the enduring power of gemstones.