December is the final month of the year, and those born in this time are traditionally associated with two birthstones: tanzanite and turquoise. These gemstones are celebrated for their vibrant colors, unique symbolism, and the ways in which they can be incorporated into fine jewelry—especially when set in gold. This article delves into the properties, history, and cultural significance of tanzanite and turquoise, as well as their role in modern December birthstone jewelry.
Historical and Cultural Significance
The December birthstones have long been associated with meaning, mysticism, and personal expression. While tanzanite is a relatively modern discovery, turquoise has been revered for thousands of years across various civilizations.
Tanzanite: A Modern Discovery
Tanzanite is a relatively recent addition to the world of gemstones. It was first discovered in 1967 in the Merelani Hills of Tanzania, a region known for its rich mineral deposits. The gemstone is a variety of the mineral zoisite, distinguished by its intense blue to violet color. Tanzanite quickly became popular in the jewelry industry due to its striking appearance and its limited geographic origin—only found in Tanzania. This exclusivity has made it a symbol of rarity and value.
The discovery of tanzanite was revolutionary not only for its visual appeal but also for its spiritual and metaphysical significance. It is often associated with intuition, truth, and emotional healing. These properties have made it a popular choice for December birthdays, where it is seen as a powerful stone for personal growth and self-awareness.
Turquoise: An Ancient Gemstone
In contrast to tanzanite, turquoise is one of the oldest known gemstones in human history. It has been used for thousands of years in jewelry, adornment, and even religious artifacts. Ancient civilizations such as the Egyptians, Chinese, and Native Americans all held turquoise in high esteem.
The name turquoise comes from the French pierre turquoise, meaning “Turkish stone,” as it was once believed to originate from the East, specifically through trade routes connected to Turkey. However, its true sources are much more diverse. Historically, turquoise was mined in the Near East and North Africa, but today, it is most commonly found in the southwestern United States, China, and Iran.
Turquoise is often associated with healing, protection, and clarity of thought. It is believed to have a calming effect on the wearer and is used in various cultures for its purported ability to ward off negative energy and bring good fortune.
Geological Formation and Sources
Understanding the formation and sources of these gemstones provides insight into their rarity and the care required in their handling and jewelry design.
Tanzanite: A Unique Geological Phenomenon
Tanzanite forms under specific geological conditions that are only found in the Merelani Hills of Tanzania. It is created when the mineral zoisite is exposed to high levels of heat and pressure, along with the presence of trace elements such as vanadium and iron. These elements are responsible for the gemstone's distinctive blue and violet hues.
Tanzanite is relatively soft compared to many other gemstones, with a hardness of 6 to 6.5 on the Mohs scale. This means it requires careful handling to avoid scratches or damage, especially when used in everyday jewelry. Tanzanite also exhibits trigonal crystal structure and is known for its strong pleochroism, meaning it displays different colors when viewed from different angles.
Due to its limited geographic source and the geological conditions required for its formation, tanzanite is considered a rare and valuable gemstone. It is often set in gold or silver to both enhance its beauty and provide structural support.
Turquoise: A Precipitation of Time
Turquoise is a phosphorus-based mineral that forms in arid environments. It is created when water percolates through the earth and carries dissolved minerals such as copper and aluminum. These minerals then combine with phosphorus and hydroxide to form turquoise. This process takes thousands to millions of years, making turquoise a naturally slow-forming gemstone.
The color of turquoise can vary widely depending on the trace elements present during its formation. The most desirable shade is a deep, even blue, but turquoise can also appear in shades of green, ranging from pale to deep emerald. The presence of matrix—the surrounding mineral material—can also affect the appearance of the gemstone, creating patterns and textures that are unique to each piece.
Turquoise is typically 6 to 6.5 on the Mohs scale, similar to tanzanite. However, it is often less durable due to its porous nature and susceptibility to chemical reactions. This means that turquoise should be handled with care and protected from harsh chemicals and excessive heat.
Gemological Properties
Understanding the physical and optical properties of tanzanite and turquoise is essential for both gemologists and jewelry buyers. These properties influence not only the appearance of the stones but also how they are set and cared for in gold jewelry.
Tanzanite: A Play of Colors
Tanzanite is known for its pleochroism, a phenomenon where the gemstone appears to change color when viewed from different angles. This effect is particularly striking in tanzanite, where the stone can display shades of blue, violet, and even burgundy. The most prized tanzanite stones are those with a deep, even blue when viewed from the top, as this color is considered the most visually appealing.
The refractive index of tanzanite ranges from 1.694 to 1.704, which gives it a moderate level of brilliance. Tanzanite also has a specific gravity of around 3.1 to 3.4, which means it is relatively dense for a gemstone of its size.
When cut into jewelry, tanzanite is often faceted to enhance its color and light return. The emerald cut and oval cut are particularly popular choices, as they allow for the display of pleochroism and provide a balanced shape that complements gold settings.
Turquoise: A Natural Stone of Charm
Turquoise is known for its unique color and texture, which can vary significantly from one piece to another. It is typically opaque to slightly translucent, with a glassy to waxy luster. The presence of matrix—the surrounding mineral material—can create interesting patterns and textures, making each piece of turquoise truly one-of-a-kind.
The refractive index of turquoise is relatively low, ranging from 1.61 to 1.65, which means it does not exhibit the same level of brilliance as harder gemstones like diamonds or sapphires. However, its distinctive color and natural beauty make it a popular choice for jewelry.
When setting turquoise in gold, it is important to consider the porosity and chemical sensitivity of the stone. Turquoise should be sealed or treated to prevent it from absorbing oils, lotions, or other substances that can dull its appearance over time. It is also important to avoid exposure to extreme temperatures, as this can cause the stone to crack or lose its color.
Symbolism and Metaphysical Beliefs
Both tanzanite and turquoise are associated with a range of symbolic and metaphysical properties, which have contributed to their popularity in December birthstone jewelry.
Tanzanite: The Stone of Intuition
Tanzanite is often referred to as the stone of intuition and truth. It is believed to enhance the wearer's ability to trust their instincts and make decisions with confidence. In metaphysical circles, tanzanite is also associated with emotional healing and transformation. It is thought to help release negative emotions and promote a sense of inner peace and balance.
Tanzanite is also connected to the third eye and throat chakras, which are believed to be the centers of intuition and communication. Wearing tanzanite is thought to help align these chakras and improve one's ability to express their thoughts and emotions clearly.
Turquoise: The Stone of Protection and Clarity
Turquoise has long been associated with protection, healing, and clarity of thought. In ancient times, it was used as a protective amulet to ward off evil spirits and negative energy. It was also believed to bring good luck and prosperity to those who wore it.
In many cultures, turquoise is considered a stone of the sky and water, representing the connection between the earth and the heavens. It is also associated with calmness, patience, and wisdom, making it a popular choice for those seeking emotional balance and mental clarity.
In modern times, turquoise is still used in spiritual and therapeutic practices, where it is believed to help reduce stress, anxiety, and emotional turmoil. It is often worn as a calming stone to promote a sense of well-being and inner harmony.
Care and Cleaning of December Birthstone Jewelry
Proper care is essential for preserving the beauty and longevity of December birthstone jewelry, especially when set in gold. Given the relatively low hardness of both tanzanite and turquoise, special care must be taken to avoid damage.
Tanzanite Care
Tanzanite should be protected from hard impacts and scratches, as it can be easily damaged. It is also sensitive to heat and chemicals, which can cause it to lose its color or become brittle.
To clean tanzanite, use a soft cloth and mild soap. Avoid using ultrasonic cleaners or steam cleaners, as these can cause the stone to crack. Tanzanite should also be stored separately from harder gemstones to prevent scratching.
When wearing tanzanite jewelry, it is best to remove it before applying lotions, perfumes, or hairsprays, as these can dull the stone's appearance over time.
Turquoise Care
Turquoise is even more sensitive than tanzanite and requires gentle handling. It should be protected from chemicals, heat, and excessive moisture, as these can cause it to crack, fade, or become discolored.
To clean turquoise, use a soft, damp cloth and mild soap. Avoid using abrasive materials or harsh chemicals, as these can damage the stone's surface. Turquoise should also be sealed or treated to prevent it from absorbing oils or lotions, which can dull its appearance.
When not in use, turquoise should be stored in a cool, dry place to prevent it from drying out or cracking. It should also be kept away from direct sunlight and extreme temperature changes.
Conclusion
December birthstone jewelry featuring tanzanite and turquoise offers a unique blend of beauty, history, and symbolism. These gemstones, though different in their origins and properties, share a common appeal that has made them popular choices for December birthdays. Tanzanite, with its deep blue and violet hues, is a symbol of intuition and truth, while turquoise, with its natural charm and vibrant color, represents protection and clarity.
When set in gold, these gemstones become even more striking, combining the warmth of the metal with the cool, calming tones of the stones. Whether worn as a personal birthstone or as a gift for a loved one, December birthstone jewelry is a meaningful and timeless expression of celebration and connection.
The care and handling of these gemstones are essential for preserving their beauty and value. By understanding their properties and following proper care guidelines, jewelry owners can enjoy their December birthstone pieces for years to come.