December, the final month of the year, is symbolically linked to the gemstone tanzanite. While the December birthstone is most commonly associated with tanzanite, the modern market also offers cubic zirconia and Swarovski crystal alternatives—particularly in children’s jewelry. These materials, while not tanzanite in composition, capture the essence of its color and allure, making them ideal for everyday wear and safe use in delicate designs such as baby and children’s earrings.
This article delves into the historical significance of tanzanite, its geological formation and sources, its gemological properties, and its evolving role in jewelry—especially in the form of earrings for children. We will also explore how the December birthstone has transitioned into contemporary jewelry markets, where alternatives like cubic zirconia and crystals are often used for their accessibility and durability.
History and Lore of the December Birthstone
Tanzanite, the primary gemstone associated with December, was first discovered in the 1960s in Tanzania—hence its name. It is a relatively modern gemstone, having been introduced to the market in the late 1960s and gaining popularity in the 1970s. Unlike many other birthstones with ancient roots, tanzanite’s history is more recent, but it has quickly become a symbol of elegance and rarity.
The gemstone’s association with December was solidified by the American National Retail Jewelers Association (ANJRA), which updated its list of birthstones in the 20th century. Before this, December was linked to turquoise, but the addition of tanzanite brought a vibrant new dimension to the month's symbolism.
While tanzanite is the primary December birthstone, it is worth noting that the month also has historical ties to turquoise and zircon. These stones have been used for centuries in various cultures, particularly in the Middle East and Asia, where they were valued for their beauty and spiritual properties. The inclusion of tanzanite into this lineage of December gems reflects the evolving nature of birthstone traditions, which have been influenced by both cultural shifts and the introduction of new gem materials.
Today, the December birthstone is not only worn as a personal symbol but also as a meaningful gift, especially for children. The rise of children’s jewelry featuring December birthstones—often in the form of earrings—has made it easier for parents to celebrate a child’s birthday with a piece of jewelry that is both stylish and meaningful.
Geological Formation and Sources
Tanzanite is a type of zoisite, a calcium aluminum silicate mineral that belongs to the epidote group. Its chemical composition is Ca₂Al₃(SiO₄)(Si₂O₇)O(OH) and it is distinguished by its trichroic nature—meaning it can display three different colors when viewed from different angles: blue, violet, and brown. Tanzanite's most prized coloration is a vivid blue to violet hue, which is achieved through heat treatment of the raw material.
The gemstone is found almost exclusively in the Merelani Hills of northern Tanzania, near the city of Arusha. This region is the world's only source of tanzanite, making it one of the rarest gemstones in the world. The geological conditions in this area—specifically the presence of vanadium and the particular metamorphic processes—create the unique coloration and crystal structure that define tanzanite.
Despite its rarity and exclusivity, tanzanite is not the only material used in December birthstone jewelry. Cubic zirconia, a synthetic gemstone, is frequently used as a cost-effective alternative, especially in children’s jewelry. It mimics the color and brilliance of tanzanite but lacks its natural formation and rarity. Cubic zirconia is a lab-created material with a chemical formula of ZrO₂ and is known for its high refractive index and dispersion, giving it a fire-like brilliance.
Swarovski crystals, another popular option, are made from leaded glass and are often used in fashion jewelry. These crystals are not gemstones in the traditional sense but are designed to imitate the look of tanzanite and other precious stones. They are highly durable and affordable, making them ideal for children's jewelry such as earrings.
The use of these alternatives in December birthstone jewelry reflects both the practical needs of the market—such as affordability and durability—and the desire to maintain the aesthetic appeal of the December birthstone.
Gemological Properties of Tanzanite and Alternatives
Tanzanite
| Property | Value |
|---|---|
| Chemical Formula | Ca₂Al₃(SiO₄)(Si₂O₇)O(OH) |
| Hardness (Mohs) | 6–7 |
| Color | Blue to violet, often trichroic |
| Refractive Index | 1.694–1.700 |
| Specific Gravity | 3.14–3.38 |
| Luster | Vitreous |
| Transparency | Transparent to translucent |
| Cleavage | Poor to indistinct |
Tanzanite is a moderately hard gemstone, with a Mohs hardness of 6–7, which makes it suitable for everyday wear in settings that protect the stone from impact. Its trichroic nature means that it must be cut carefully to display the most desirable color. Typically, tanzanite is faceted to emphasize the blue or violet tones, with the brown coloration removed from the visible side.
Its refractive index is relatively high, which contributes to its brilliance and fire. Tanzanite is also sensitive to heat and light, so it must be handled with care during cutting and setting. Despite its beauty, tanzanite requires protection from physical stress and harsh chemicals, making it a less ideal choice for children’s jewelry.
Cubic Zirconia
| Property | Value |
|---|---|
| Chemical Formula | ZrO₂ |
| Hardness (Mohs) | 8–8.5 |
| Color | Available in various hues, including blue |
| Refractive Index | 2.15–2.18 |
| Specific Gravity | 5.6–6.0 |
| Luster | Adamantine |
| Transparency | Transparent |
| Cleavage | None |
Cubic zirconia is a synthetic gemstone with a higher hardness than tanzanite, making it more durable for everyday wear. It is often used to mimic the color and brilliance of tanzanite, especially in children’s jewelry. Its refractive index is significantly higher than that of tanzanite, giving it a more brilliant and fiery appearance.
Cubic zirconia is also more resistant to heat and chemicals than tanzanite, which makes it a safer and more practical option for children’s jewelry. However, it is not as rare or valuable as tanzanite, and its synthetic nature means it lacks the natural geological history that contributes to the allure of tanzanite.
Swarovski Crystals
| Property | Value |
|---|---|
| Chemical Composition | Leaded glass |
| Hardness (Mohs) | 5–6 |
| Color | Available in a wide range, including blue |
| Refractive Index | 2.15–2.18 |
| Luster | Vitreous |
| Transparency | Transparent |
| Cleavage | None |
Swarovski crystals are not gemstones but are designed to imitate the look of precious and semi-precious stones. They are made from leaded glass and are known for their high refractive index and brilliance. While they do not have the same chemical or physical properties as tanzanite, they are often used in fashion jewelry to achieve a similar aesthetic at a lower cost.
Swarovski crystals are especially popular in children’s jewelry because they are lightweight, durable, and hypoallergenic. They are also easy to clean and maintain, making them ideal for everyday wear.
Symbolism and Cultural Significance of December Birthstone
The December birthstone, particularly tanzanite, is associated with a range of meanings and properties in various cultures and traditions. In modern gemology and metaphysical practices, tanzanite is believed to promote emotional healing, intuition, and spiritual awareness. It is often used in meditation and is said to help with emotional balance and the release of fear or anxiety.
In ancient times, before tanzanite was discovered, December was associated with turquoise and zircon. Turquoise was highly valued in ancient Egypt and the Middle East for its protective properties and was often used in amulets and talismans. Zircon, which can display a wide range of colors, was also used in early jewelry and was believed to have mystical properties, including the ability to ward off nightmares and enhance wisdom.
The introduction of tanzanite into the December birthstone tradition in the 20th century brought new symbolic meanings to the month. As a relatively new gemstone, tanzanite is often associated with discovery, rarity, and the idea of something unique and precious. Its deep blue and violet hues are also linked to themes of depth, mystery, and transformation.
Today, the December birthstone is not only a symbol of personal identity and celebration of a birth month but also a meaningful gift that can be passed down through generations. The rise of children’s jewelry featuring the December birthstone has made it possible for even the youngest members of a family to wear and celebrate their own birthstone, reinforcing the tradition and its significance.
Care and Maintenance of December Birthstone Earrings
When it comes to caring for December birthstone earrings, the material used is a key factor in determining the appropriate cleaning and maintenance methods. Each material—tanzanite, cubic zirconia, and Swarovski crystals—requires slightly different care to ensure longevity and beauty.
Tanzanite
Tanzanite is a relatively soft gemstone and should be handled with care. It is sensitive to heat and should not be exposed to high temperatures, such as steam or boiling water. It is also vulnerable to scratches from harder materials, so it should be stored separately from other gemstones.
To clean tanzanite earrings, a soft cloth and a mild soap solution can be used. A gentle brush can help remove dirt from the facets, but abrasive materials should be avoided. Ultrasonic and steam cleaners are generally not recommended for tanzanite, as they can cause damage.
Cubic Zirconia
Cubic zirconia is a harder and more durable material than tanzanite, making it easier to care for. It can be cleaned with warm, soapy water and a soft cloth or brush. Ultrasonic cleaners are generally safe for cubic zirconia, although it is always best to consult the manufacturer's guidelines before using them.
Cubic zirconia is less sensitive to heat than tanzanite, but it is still advisable to avoid exposure to extreme temperatures. It is also less prone to scratches, making it a good choice for children’s jewelry that may be worn frequently and handled roughly.
Swarovski Crystals
Swarovski crystals are highly durable and can be cleaned with a soft cloth and mild soap. They are also resistant to scratches and do not require special handling. However, it is important to avoid using harsh chemicals or abrasive materials, as these can dull the surface of the crystals.
Because Swarovski crystals are made from leaded glass, they should not be exposed to high heat for prolonged periods. They are, however, ideal for everyday wear and can be easily maintained with regular cleaning.
Conclusion
The December birthstone, whether in the form of tanzanite, cubic zirconia, or Swarovski crystals, holds a special place in the world of gemstones and jewelry. Its association with the end of the year and the idea of new beginnings makes it a symbol of transformation and celebration. The introduction of this gemstone into the December birthstone tradition in the 20th century brought a vibrant new dimension to the month's symbolism.
Today, the December birthstone is not only a personal symbol for adults but also a meaningful way to celebrate a child’s birth month. The rise of children’s jewelry featuring the December birthstone—particularly in the form of earrings—has made it possible for even the youngest members of a family to wear and celebrate their own birthstone.
Whether as a natural gemstone or a synthetic or crystal alternative, the December birthstone continues to capture the imagination and inspire creativity in jewelry design. Its beauty, symbolism, and versatility make it a cherished gem that is sure to remain a beloved part of the birthstone tradition for years to come.