December, the month of celebration and renewal, is symbolically represented by two zodiac signs: Sagittarius and Capricorn. Those born under Sagittarius, from November 22 to December 21, are characterized by their adventurous spirit, optimism, and philosophical curiosity. The December birthstones associated with Sagittarius reflect these dynamic traits while offering symbolic and metaphysical significance. Among the most prominent are tanzanite, turquoise, and zircon, each with its own unique history, geological origin, and cultural resonance.
This article explores the significance of these December birthstones for Sagittarius, delving into their historical uses, gemological properties, and the cultural and metaphysical meanings attributed to them. We will also provide practical care instructions to help preserve these precious stones.
History and Lore
The concept of birthstones dates back to biblical times, with references to the 12 stones of Aaron’s breastplate in the Old Testament. However, the standardized list of birthstones we recognize today was established in 1912 by the American National Association of Jewelers. This list was later revised in 1952 by the American Gemological Trade Association (AGTA), which is now the American Gem Trade Association (AGTA). These updates reflect the evolving nature of gemstone appreciation and market trends.
Sagittarius, being a sign that spans both November and December, inherits several birthstones. The most notable among them is tanzanite, which was officially added as a December birthstone in 2002 by the American Gem Trade Association. Tanzanite is relatively new to the birthstone tradition, having been discovered in Tanzania in 1967. Its vibrant blue-violet color and limited geographic source make it a symbol of transformation and spiritual awakening.
Turquoise, on the other hand, has a far longer and more storied history. It was recognized as a December birthstone in 1912 and is associated with the 11th wedding anniversary. Turquoise has been used for thousands of years across multiple civilizations, from ancient Egypt to the American Southwest. It was considered a sacred stone in many cultures and was often used in amulets and ceremonial objects. The Maasai people of East Africa, for example, believed that a bolt of lightning struck the earth and transformed the rocks into the beautiful blue and green hues of turquoise.
Zircon is another December birthstone associated with Sagittarius. Known for its brilliance and variety of colors, zircon has been used in jewelry for centuries. The colorless form of zircon is sometimes used as a diamond substitute due to its high refractive index. Zircon is also notable for being the oldest known mineral on Earth, with some crystals dating back nearly 4.4 billion years.
Geological Formation and Sources
Understanding the geological origins of a gemstone provides insight into its rarity and value. The December birthstones for Sagittarius—tanzanite, turquoise, and zircon—each have distinct formation processes and geographic sources.
Tanzanite
Tanzanite is a relatively rare gemstone that is found only in a small area of Tanzania, near the base of Mount Kilimanjaro. It is a variety of the mineral columbite, and its striking blue-violet color is due to the presence of violet and blue pleochroism, meaning it displays different colors when viewed from different angles. The coloration is caused by trace amounts of vanadium and is enhanced by heat treatment.
Tanzanite forms in metamorphic rocks, specifically in limestone and granite. The unique geological conditions of the area where tanzanite is found—where granite intrudes into limestone—create the chemical environment necessary for its formation. The gemstone was first discovered in 1967 by Jude Kamusi, a local Maasai herder, and was later marketed as the "stone of transformation."
Turquoise
Turquoise is a phosphate mineral composed of copper and aluminum, and it forms in low-temperature environments, typically in veins and cavities within sedimentary rocks. The presence of copper gives turquoise its characteristic blue color, while iron imparts green tones. The gemstone is often found in arid regions, where mineral-rich water seeps through the rock and deposits the necessary elements.
The most significant sources of turquoise today include Tanzania, China, Nepal, Egypt, and the United States (particularly Arizona, New Mexico, and Nevada). Historically, Persia (modern-day Iran) was one of the most renowned sources of turquoise, with deposits dating back to at least 7000 BCE. Ancient Egyptian artisans used turquoise from these Persian mines to create amulets and jewelry, often associating it with the goddess Hathor, the goddess of love, music, and turquoise.
Zircon
Zircon is a zirconium silicate mineral that is found in a wide range of colors, including colorless, blue, yellow, red, and green. The blue variety is particularly popular in jewelry and is often referred to as Star Blue Zircon. The coloration of zircon is due to natural radiation, and it is often enhanced through heat treatment.
Zircon forms in igneous rocks, particularly in granite and basalt, and is also found in metamorphic and sedimentary deposits. It is one of the oldest minerals on Earth, with some zircon crystals found in Australia dating back 4.4 billion years. This makes zircon one of the most important minerals for geologists studying the early Earth.
The most significant sources of zircon today include Sri Lanka, India, Myanmar, Madagascar, and Brazil. In the United States, zircon is found in California and Utah. The mineral is also mined in Australia, where it plays a role in the nuclear industry due to its resistance to radiation.
Gemological Properties
The gemological properties of a stone—such as its hardness, refractive index, color, and clarity—determine its suitability for jewelry and its overall value. Below is a detailed breakdown of the gemological properties of the December birthstones for Sagittarius.
Tanzanite
- Chemical Formula: Ca₂Al₃(PO₄)₃(OH)₃
- Color: Blue to violet, with strong pleochroism
- Hardness (Mohs Scale): 6–7
- Refractive Index: 1.694–1.700
- Specific Gravity: 3.10–3.35
- Cleavage: Distinct
- Transparency: Transparent to translucent
- Luster: Vitreous
- Cut: Typically cut to enhance its pleochroism, often in cushion or oval shapes
Tanzanite is a relatively soft gemstone, so it is best suited for everyday wear in well-protected settings. Its high refractive index gives it a bright, lively appearance, and its pleochroism means that the color can appear different when viewed from different angles. Tanzanite is often heat-treated to enhance its color, and this treatment is considered stable and permanent.
Turquoise
- Chemical Formula: CuAl₆(PO₄)₄(OH)₈·4H₂O
- Color: Blue to green, depending on the concentration of copper and iron
- Hardness (Mohs Scale): 5–6
- Refractive Index: 1.61–1.65
- Specific Gravity: 2.60–2.80
- Cleavage: None
- Transparency: Opaque to translucent
- Luster: Waxy to greasy
- Cut: Often carved or cabochon-cut to emphasize color and pattern
Turquoise is a relatively soft and porous gemstone, which makes it sensitive to oils, lotions, and acidic substances. It is best suited for low-wear settings and should be protected from exposure to harsh chemicals. Its waxy luster and chatoyancy (a cat’s eye effect in some stones) make it a unique and desirable gemstone.
Zircon
- Chemical Formula: ZrSiO₄
- Color: Colorless, blue, yellow, red, green
- Hardness (Mohs Scale): 6–7.5
- Refractive Index: 1.92–2.01
- Specific Gravity: 4.6–4.7
- Cleavage: Perfect
- Transparency: Transparent to translucent
- Luster: Vitreous
- Cut: Often cut to maximize brilliance, with popular shapes including round, princess, and emerald
Zircon is known for its high refractive index and dispersion, which gives it a fiery brilliance similar to diamonds. The blue variety, known as Star Blue Zircon, is particularly popular in jewelry. However, zircon has perfect cleavage, which makes it prone to chipping and requires careful setting in jewelry. It is also sensitive to heat and light, so exposure to high temperatures can cause the color to fade or change.
Symbolism and Metaphysical Beliefs
The December birthstones for Sagittarius are not only prized for their beauty and rarity but also for their rich symbolism and metaphysical properties. These gemstones have been associated with various meanings across different cultures and eras.
Tanzanite
Tanzanite is often referred to as the "stone of transformation" due to its association with spiritual awakening, intuition, and emotional healing. It is believed to help individuals release old patterns and embrace new beginnings. In metaphysical practices, tanzanite is said to activate the throat, third-eye, and crown chakras, allowing for enhanced communication with higher dimensions and improved psychic abilities.
The Maasai people of Tanzania, where the gemstone is found, give tanzanite as a gift to newborns as a symbol of health, well-being, and prosperity. It is also believed to strengthen the immune system, detoxify the blood, and regenerate cells, skin, and hair.
Turquoise
Turquoise has long been considered a stone of protection, harmony, and abundance. It is believed to calm the mind, enhance intuition, and provide emotional stability. In many indigenous cultures, turquoise is used in ceremonial jewelry and amulets to ward off negative energies and promote spiritual clarity.
Ancient Egyptians associated turquoise with the goddess Hathor, who was considered a protector of travelers and a symbol of joy and fertility. In the American Southwest, turquoise is still used in Native American jewelry and is considered a stone of good fortune and protection. It is also believed to enhance communication and promote a sense of balance and well-being.
Zircon
Zircon is often associated with clarity of thought, wisdom, and spiritual growth. It is believed to enhance memory, improve focus, and help individuals make wise decisions. In some traditions, zircon is considered a stone of the stars, representing the divine connection between the earth and the cosmos.
Due to its radiation resistance and ancient origins, zircon is also seen as a stone of endurance and longevity. It is believed to protect the wearer from negative energies and promote a deep sense of inner peace and stability.
Care and Cleaning
Proper care and cleaning are essential to maintaining the beauty and longevity of any gemstone. The following are recommended care practices for the December birthstones for Sagittarius.
Tanzanite
- Avoid sudden or extreme temperature changes, as tanzanite can be sensitive to thermal shock.
- Avoid ultrasonic and steam cleaners, which can damage the stone or cause it to fracture.
- Clean with warm, soapy water and a soft brush, then gently dry with a soft cloth.
- Store separately from other gemstones to prevent scratches.
Turquoise
- Avoid exposure to harsh chemicals, oils, and lotions, which can discolor or damage the stone.
- Clean with a soft cloth and mild soap and water, avoiding abrasive materials.
- Avoid prolonged exposure to sunlight or heat, as this can cause the stone to fade or dry out.
- Store in a dry, cool place to prevent moisture-related damage.
Zircon
- Avoid ultrasonic and steam cleaners, especially for zircon with perfect cleavage, as these can cause the stone to chip or fracture.
- Clean with warm, soapy water and a soft brush, then gently dry with a soft cloth.
- Store separately from other gemstones to prevent scratches.
- Avoid exposure to high heat, as zircon can be sensitive to thermal changes.
Conclusion
The December birthstones for Sagittarius—tanzanite, turquoise, and zircon—offer a rich tapestry of historical significance, gemological properties, and metaphysical meaning. Each of these gemstones has a unique story and a set of characteristics that make them ideal for those born under the zodiac sign of Sagittarius.
Tanzanite, with its vibrant blue-violet color and rarity, symbolizes transformation, intuition, and spiritual awakening. It is a relatively modern gemstone but has quickly gained popularity due to its beauty and symbolic significance.
Turquoise, one of the oldest and most revered gemstones, represents protection, harmony, and emotional balance. Its soft, waxy luster and chatoyancy make it a timeless favorite in both ancient and contemporary jewelry.
Zircon, with its high refractive index and fiery brilliance, is a stone of wisdom, clarity, and endurance. Its ancient origins and radiation resistance make it a symbol of strength and longevity.
Whether you are a jewelry buyer, gemstone enthusiast, or student of gemology, the December birthstones for Sagittarius offer a fascinating glimpse into the world of gemstones and their enduring appeal.