For those born in December, the month is not only a time of celebration and reflection but also a unique opportunity to connect with a selection of gemstones that reflect the season’s chill and charm. December is the only month with four officially recognized birthstones: Turquoise, Zircon, Tanzanite, and Blue Topaz. These gemstones, though distinct in their properties and origins, are united by their cool blue tones and rich symbolic meanings—ranging from protection and wisdom to transformation and clarity.
The inclusion of multiple birthstones for a single month is a rare phenomenon, and December’s selection reflects both historical traditions and modern discoveries. Each of these gemstones has its own story, rooted in centuries of cultural significance and gemological evolution. Understanding these stones—how they form, where they are found, and what they represent—offers a deeper appreciation for their beauty and value.
This article explores the December birthstones in detail, covering their historical roots, gemological properties, symbolic meanings, and practical considerations for care and use. The goal is to provide a comprehensive and authoritative guide for gemstone enthusiasts, jewelry buyers, and students of gemology.
History and Lore of December’s Birthstones
Turquoise: A Stone of Ancient Significance
Turquoise is one of the oldest known gemstones, with a history that stretches back thousands of years. It was highly valued by ancient civilizations such as the Egyptians, who used it in jewelry and amulets to ward off evil and ensure good fortune. In many cultures, turquoise was believed to possess protective and healing properties, often worn as a talisman against illness and misfortune.
The stone’s name comes from the French word turquoise, meaning “Turkish,” as it was once believed to originate from the Middle East and be transported through Turkey. In reality, turquoise is formed through a complex chemical process involving the oxidation of copper and the hydration of aluminum phosphate. The resulting material is typically found in arid regions, such as the southwestern United States, Iran, and Egypt.
Tanzanite: A Modern Discovery
Tanzanite is a relatively new gemstone in the world of jewelry, first discovered in 2002 in Tanzania. Unlike the ancient allure of turquoise, tanzanite was only recently recognized for its beauty and rarity. It is a type of zoisite, a mineral that can display a range of colors depending on the angle of light. Tanzanite is particularly prized for its deep violet-blue color, which is enhanced through heat treatment.
The stone’s limited geographic source—only found in a specific region of Tanzania—makes it one of the rarest gemstones in the world. This scarcity, combined with its striking color, has made tanzanite a symbol of transformation and new beginnings. It is often given as a gift during significant life events, such as weddings or career changes, to encourage courage and clarity.
Zircon: A Sparkling Symbol of Clarity
Zircon is another gemstone with a long and varied history. While it is often mistaken for diamonds due to its high refractive index and brilliance, zircon has its own unique characteristics. The stone has been used in jewelry for centuries, particularly in ancient Mesopotamia and India.
Zircon comes in a wide range of colors, but the blue variety—often referred to as “blue zircon”—is especially popular among December birthstone enthusiasts. This coloration is typically the result of heat treatment. Zircon is also believed to have metaphysical properties, such as enhancing mental clarity and promoting wisdom and balance.
Blue Topaz: A Durable Winter Gem
Blue topaz is the newest addition to the December birthstone lineup. Unlike its counterparts, blue topaz is not found in nature in its blue form. Instead, it is a colorless mineral that is treated with irradiation or heat to produce its beautiful blue color. This treatment does not alter the stone’s structure or durability, making it a popular choice for everyday jewelry.
Blue topaz is known for its clarity, calmness, and durability. With a hardness of 8 on the Mohs scale, it is one of the most resilient December birthstones. It was officially added to the list of December birthstones to provide a more affordable and versatile option for jewelry design.
Geological Formation and Sources
Turquoise: A Product of Arid Environments
Turquoise is a hydrated phosphate of aluminum and copper, with the chemical formula CuAl₆(PO₄)₄(OH)₈·4H₂O. It forms in the oxidation zones of copper deposits, typically in arid or semi-arid regions. The presence of copper gives the stone its characteristic blue or green color, while the hydration of the mineral affects its overall appearance.
Major sources of turquoise include the United States (particularly Arizona and Nevada), Iran, China, and Egypt. These regions provide a range of colors and patterns, from pale blue to deep greenish-blue, often with matrix patterns that enhance the stone’s uniqueness.
Tanzanite: A Unique Geological Phenomenon
Tanzanite is a type of zoisite, a silicate mineral with the chemical formula Ca₂Al₃(SiO₄)(Si₂O₇)O(OH) with the addition of trace amounts of vanadium. The deep blue-violet color of tanzanite is due to the presence of vanadium and the stone’s trichroic nature—meaning it can display three different colors depending on the angle of light.
Tanzanite is found exclusively in the Merelani Hills of Tanzania, near Mount Kilimanjaro. The geological conditions required to form tanzanite are extremely rare, making it one of the most geologically unique gemstones in the world. This limited source ensures that tanzanite remains a highly sought-after and valuable gemstone.
Zircon: A Diverse and Durable Gem
Zircon is a zirconium silicate with the chemical formula ZrSiO₄. It is found in a variety of geological environments, including metamorphic and igneous rocks. Zircon is known for its high refractive index and dispersion, which give it a diamond-like sparkle. It is also one of the oldest minerals on Earth, with some zircon crystals dating back over 4 billion years.
Blue zircon is created through heat treatment, which stabilizes the stone’s color and enhances its brilliance. Major sources of zircon include Australia, Thailand, Cambodia, and Brazil. The durability and affordability of blue zircon make it a popular choice for jewelry.
Blue Topaz: A Human-Created Beauty
Blue topaz is a type of topaz, a silicate mineral with the chemical formula Al₂SiO₄(F,OH)₂. In its natural form, topaz is colorless or yellow. The blue coloration is achieved through a combination of irradiation and heat treatment, a process that does not affect the stone’s hardness or clarity.
Blue topaz is found in various parts of the world, including Brazil, Nigeria, and the United States. Texas even recognizes blue topaz as its official state gem. This treatment process allows for consistent coloration, making blue topaz a reliable and attractive option for jewelry.
Gemological Properties of December Birthstones
| Gemstone | Color | Hardness (Mohs) | Chemical Composition | Refractive Index | Cut | Care Instructions |
|---|---|---|---|---|---|---|
| Turquoise | Blue, greenish-blue | 5–6 | CuAl₆(PO₄)₄(OH)₈·4H₂O | 1.61–1.65 | Cabochon | Avoid heat and harsh chemicals |
| Tanzanite | Violet-blue | 6–7 | Ca₂Al₃(SiO₄)(Si₂O₇)O(OH) | 1.69–1.70 | Facet | Store separately and avoid direct sunlight |
| Zircon | Blue, yellow, colorless | 6–7.5 | ZrSiO₄ | 1.92–2.01 | Facet | Avoid ultrasonic cleaning |
| Blue Topaz | Blue | 8 | Al₂SiO₄(F,OH)₂ | 1.62 | Facet | Can be cleaned with ultrasonic |
This table provides a clear comparison of the physical and optical properties of the four December birthstones. Each gemstone has its own unique characteristics that affect its use in jewelry and care requirements.
Symbolism and Metaphysical Beliefs
Turquoise: A Stone of Protection and Calm
Turquoise is often associated with protection, wisdom, and calm. In many ancient cultures, it was believed to have the power to ward off evil spirits and protect the wearer from harm. It is also considered a stone of good fortune, often used in talismans and amulets.
In modern times, turquoise is believed to help with emotional balance and mental clarity. It is particularly recommended for those experiencing stress or anxiety. Its cool blue color is thought to have a calming effect on the mind and body.
Tanzanite: A Stone of Transformation and Clarity
Tanzanite is linked to transformation and new beginnings. It is believed to help individuals navigate change with grace and clarity. The stone is also associated with emotional healing and spiritual growth, making it a popular choice for those undergoing personal or professional transformations.
Its deep blue-violet color is often seen as a symbol of wisdom and intuition. Many believe that tanzanite enhances one’s ability to trust their instincts and make decisions with confidence.
Zircon: A Stone of Wisdom and Focus
Zircon is known for its ability to enhance mental clarity and focus. It is often used by those who need to stay sharp and focused, such as students, professionals, and creatives. Zircon is also associated with balance and harmony, helping to bring stability to both mind and body.
In many cultures, zircon is believed to promote good health and longevity. It is also considered a stone of truth, encouraging honesty and self-awareness.
Blue Topaz: A Stone of Calm and Clarity
Blue topaz is associated with calmness, serenity, and emotional balance. It is often recommended for those who need to find peace in chaotic or stressful situations. The stone is believed to help clear the mind and promote a sense of inner peace.
In addition to its calming properties, blue topaz is also linked to wisdom and clarity. It is often used in meditation and spiritual practices to enhance focus and insight.
Care and Cleaning of December Birthstones
Turquoise
Turquoise is a relatively soft gemstone (5–6 on the Mohs scale), and it is also porous, which makes it susceptible to damage from heat and chemicals. To care for turquoise jewelry, avoid exposing it to direct sunlight, heat, or moisture. It is best to clean it with a soft, dry cloth and avoid using harsh chemicals or ultrasonic cleaners.
Tanzanite
Tanzanite is a bit more durable than turquoise (6–7 on the Mohs scale), but it is still sensitive to heat and light. Prolonged exposure to direct sunlight can cause the color to fade over time. It is best to store tanzanite in a dark place when not in use.
When cleaning tanzanite, use a soft cloth and mild soap with warm water. Avoid using ultrasonic cleaners or steamers, as they can damage the stone’s color and structure.
Zircon
Zircon is a relatively hard gemstone (6–7.5 on the Mohs scale) and is generally durable. However, it is still best to avoid using ultrasonic cleaners, as they can cause damage to the stone. Zircon can be cleaned with warm soapy water and a soft cloth.
To preserve its brilliance, it is best to store zircon separately from other gemstones to prevent scratches. Zircon should also be removed before engaging in physical activities or wearing strong perfumes or lotions.
Blue Topaz
Blue topaz is the hardest of the four December birthstones, with a hardness of 8 on the Mohs scale. This makes it one of the most durable and practical gemstones for everyday wear.
Blue topaz can be cleaned with warm soapy water or even an ultrasonic cleaner. It is also resistant to fading and can be worn frequently without losing its color or luster.
Conclusion
December’s birthstones offer a rich and diverse selection of gemstones, each with its own unique history, properties, and symbolism. From the ancient allure of turquoise to the modern rarity of tanzanite, these stones reflect the beauty and complexity of the world of gemology.
Whether you are a gemstone enthusiast, a jewelry buyer, or a student of gemology, the December birthstones provide a fascinating glimpse into the world of colored gemstones. Their cool blue tones and deep symbolic meanings make them not only beautiful but also meaningful choices for jewelry and personal adornment.
Understanding the properties, history, and care requirements of these gemstones allows you to appreciate them on a deeper level and enjoy their beauty for years to come.