December, the final month of the year, is associated with three distinct gemstones: turquoise, tanzanite, and sky blue topaz. Each of these stones carries its own unique history, meaning, and aesthetic appeal. Whether for personal adornment or as a meaningful gift, December birthstones have long been cherished for their beauty and symbolic significance. This article explores the gemological properties, historical origins, cultural symbolism, and care instructions for these three birthstones, all supported by the information provided in the sources.
December is the only birth month associated with three different gemstones, a reflection of the diverse range of blue hues and their rich symbolic meanings. Each of these stones—turquoise, tanzanite, and sky blue topaz—has its own distinct characteristics and history. This guide will examine their properties, meanings, and how to best care for them.
History and Lore
The tradition of assigning gemstones to specific months dates back to ancient times. The earliest known reference to birthstones is found in the Breastplate of Aaron from the biblical Book of Exodus, which listed 12 stones, each associated with a tribe of Israel. Over time, these associations evolved, and by the 18th and 19th centuries, modern birthstone traditions had begun to take shape.
Turquoise
Turquoise is one of the oldest known gemstones to be used by humans, with archaeological evidence of its use dating back over 6,000 years. Ancient Egyptians referred to it as the "stone of the gods" and used it in jewelry and amulets. Pharaohs and nobles adorned themselves with turquoise to signify status and divine favor.
In Mesoamerican cultures, the Aztecs and Maya valued turquoise highly, often using it in ritual masks and ceremonial objects. Native American tribes, particularly the Navajo and Zuni, have long used turquoise in their jewelry and spiritual practices. To them, it was a protective stone that brought health, good fortune, and harmony.
The stone's association with December was formalized in the 19th and 20th centuries, as modern birthstone traditions began to emerge and evolve.
Tanzanite
Tanzanite is the youngest of the three December birthstones, having been discovered in the 1960s in Tanzania. It was first identified in 1967 by a German mineralogist, and it was named after its country of origin. Tanzanite quickly became a popular gemstone due to its striking blue-violet color and its relatively short supply—being found only in a small area near Mount Kilimanjaro.
Tanzanite symbolizes transformation, intuition, and spiritual insight. Its recent discovery has made it a modern gemstone with a unique appeal. Unlike turquoise and topaz, which have ancient histories, tanzanite is a relatively new addition to the birthstone tradition, gaining widespread recognition in the late 20th century.
Sky Blue Topaz
Topaz is an ancient gemstone with a long history in jewelry and decoration. The sky blue variant, which is the December birthstone, has a more recent origin in terms of its popularity. Historically, topaz was believed to have healing properties and was thought to bring wisdom, good fortune, and success. The name "topaz" comes from the Greek word topazios, referring to an island in the Red Sea where a different gemstone was once found.
Sky blue topaz is a heat-treated version of yellow topaz and is known for its clarity and brilliance. Its association with December is part of the modern birthstone tradition and reflects its popularity as a colorful, affordable gemstone.
Geological Formation and Sources
Each of the three December birthstones has a distinct geological origin and is found in different parts of the world. Understanding how these stones are formed and where they are sourced provides insight into their rarity and availability.
Turquoise
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, often in arid climates where water percolates through the rock and creates the conditions for turquoise to develop. The presence of copper gives turquoise its characteristic blue color, while iron imparts a greenish tint.
Historically, the finest turquoise has been mined in Iran, China, and Egypt, with more recent sources including the United States (particularly Nevada and New Mexico) and Mexico. Turquoise often contains veins of matrix, which are the remnants of the host rock. The amount and type of matrix can affect the stone's value and appearance.
Tanzanite
Tanzanite is a type of zoisite that has been heat-treated to produce its signature blue-violet color. Its chemical composition is Ca₂Al₃(SiO₄)(OH) and it is found only in Tanzania, near the base of Mount Kilimanjaro. This limited geographic source makes tanzanite one of the rarest gemstones in the world.
The gemstone forms in metamorphic rock under high heat and pressure. The original brownish zoisite is treated at high temperatures to enhance its color, a process that is now widely accepted and standard in the industry. The resulting blue and violet hues are permanent and do not fade.
Sky Blue Topaz
Topaz is a silicate mineral with the chemical formula Al₂SiO₄(F,OH)₂. Sky blue topaz is created through a process called irradiation and heat treatment. Naturally occurring topaz is usually colorless, yellow, or brown. To create the blue color, the stone is exposed to radiation and then heated, which alters the atomic structure and creates the blue hue.
The finest sky blue topaz is mined in Brazil, which is the primary source of high-quality topaz. The gemstone is relatively abundant and affordable, making it a popular choice for jewelry.
Gemological Properties
Understanding the gemological properties of each December birthstone is essential for both collectors and consumers. These properties include hardness, refractive index, specific gravity, and other characteristics that influence the stone's durability and appearance.
Turquoise
- Hardness (Mohs scale): 5 to 6
- Refractive Index: 1.61 to 1.65
- Specific Gravity: 2.6 to 2.8
- Color: Blue to green, with veins of matrix
- Transparency: Opaque to semi-transparent
- Luster: Waxy to greasy
- Cleavage: None
- Fracture: Uneven
- Chemical Stability: Sensitive to acids and heat
Turquoise is relatively soft and porous, which makes it vulnerable to damage from harsh chemicals and extreme temperatures. It is often stabilized with resins to improve its durability.
Tanzanite
- Hardness (Mohs scale): 6 to 7
- Refractive Index: 1.694 to 1.704
- Specific Gravity: 3.1 to 3.5
- Color: Blue to violet (often with pleochroism)
- Transparency: Transparent to translucent
- Luster: Vitreous
- Cleavage: Poor in one direction
- Fracture: Conchoidal
- Chemical Stability: Sensitive to heat and acids
Tanzanite is known for its pleochroism, meaning it displays different colors when viewed from different angles. It is relatively durable but can crack under high heat or sudden temperature changes.
Sky Blue Topaz
- Hardness (Mohs scale): 8
- Refractive Index: 1.61 to 1.63
- Specific Gravity: 3.4 to 3.6
- Color: Sky blue (due to irradiation and heat treatment)
- Transparency: Transparent
- Luster: Vitreous
- Cleavage: Poor in one direction
- Fracture: Conchoidal
- Chemical Stability: Stable
Sky blue topaz is one of the hardest of the three December birthstones, making it suitable for everyday wear. Its high hardness and durability make it a popular choice for rings and pendants.
Symbolism and Metaphysical Beliefs
Each December birthstone carries its own set of symbolic meanings and metaphysical properties, many of which have been passed down through centuries of tradition.
Turquoise
Turquoise has long been associated with protection, healing, and communication. It is believed to promote calmness and mental clarity. In many ancient cultures, turquoise was used in rituals and as a protective talisman. It was thought to ward off evil spirits and bring good luck to the wearer.
In modern times, turquoise is also associated with spiritual awakening and emotional balance. It is often used in meditation and energy healing practices.
Tanzanite
Tanzanite is known for its transformative properties. It is believed to enhance intuition and spiritual insight, helping the wearer to connect with their higher self. It is also associated with emotional healing and the ability to let go of past pain.
In metaphysical circles, tanzanite is often used for chakra alignment, particularly the heart and third eye chakras. It is thought to open the mind to new possibilities and promote inner peace.
Sky Blue Topaz
Sky blue topaz is associated with wisdom, success, and good fortune. It is believed to enhance mental clarity and encourage a positive outlook. It is also thought to promote emotional balance and reduce stress.
In modern crystal healing, sky blue topaz is used to stimulate creativity and focus. It is particularly valued for its calming effect and its ability to bring a sense of peace and serenity to the wearer.
Care and Cleaning
Proper care is essential for preserving the beauty and longevity of December birthstone jewelry. Each gemstone has specific care requirements based on its hardness, chemical stability, and sensitivity to heat and light.
Turquoise
Turquoise is relatively soft and porous, so it requires gentle handling. It should be protected from exposure to water, heat, and harsh chemicals. Avoid using ultrasonic or steam cleaners, as these can damage the stone.
To clean turquoise, use a soft, dry cloth to remove dust and dirt. If necessary, it can be gently wiped with a damp cloth using mild soap and water. Store turquoise away from other jewelry to prevent scratches and abrasions.
Tanzanite
Tanzanite is more durable than turquoise but still requires careful handling. It should be kept away from high heat and sudden temperature changes, as these can cause it to crack. Avoid exposure to strong acids, as tanzanite is sensitive to chemical damage.
To clean tanzanite, use warm, soapy water and a soft cloth. Avoid using ultrasonic or steam cleaners, as these can damage the stone's structure. Store tanzanite separately from other jewelry to prevent scratches.
Sky Blue Topaz
Sky blue topaz is the hardest of the three December birthstones, making it suitable for everyday wear. It is also more chemically stable and less sensitive to heat and light.
To clean sky blue topaz, use warm, soapy water and a soft cloth. Ultrasonic and steam cleaners are generally safe for this gemstone. Store sky blue topaz separately from other jewelry to prevent scratches.
Conclusion
December is a month associated with three distinct gemstones—turquoise, tanzanite, and sky blue topaz—each with its own unique history, meaning, and beauty. Whether you are drawn to the deep blue of turquoise, the vibrant blue-violet of tanzanite, or the brilliant clarity of sky blue topaz, these stones offer something for every taste and occasion.
Understanding the gemological properties, historical significance, and care requirements of each stone is essential for making an informed choice when selecting December birthstone jewelry. Whether as a meaningful gift or a personal keepsake, these gemstones continue to be cherished for their beauty and symbolic power.