December is the only month with four official birthstones, making it a unique and vibrant chapter in the story of gemstones. These gemstones—blue topaz, tanzanite, turquoise, and lapis lazuli (alongside blue zircon in some modern designations)—are celebrated for their striking colors, symbolic meanings, and rich historical significance. While blue topaz is often the most prominent December birthstone in jewelry, the month’s collection encompasses a spectrum of styles and meanings, each with its own geological and cultural story.
This article explores the December birthstones in detail, focusing on their gemological properties, historical and cultural significance, and practical care tips. We will also highlight how these gems have been embraced in jewelry design, particularly in rings, earrings, and pendants.
History and Lore of December Birthstones
Blue Topaz: A Stone of Clarity and Loyalty
Blue topaz, the most widely recognized December birthstone, has long been associated with wisdom, honesty, and calmness. Ancient Greeks believed topaz brought courage and protected against poison, while in the Middle Ages, it was thought to heal ailments and promote mental clarity. The blue coloration of modern blue topaz is the result of heat treatment and irradiation, which transforms yellow or brown natural topaz into a brilliant blue gemstone.
Although blue topaz is the modern primary birthstone for December, it is often paired with diamonds in jewelry settings, as seen in collections from brands like JamesAllen.com and WeilJewelry. These pairings create elegant designs that balance blue topaz’s icy brilliance with the classic sparkle of diamonds.
Tanzanite: A Gem of the 20th Century
Discovered in 1967 in Tanzania, tanzanite is a relatively recent addition to the gemstone world. Its discovery was serendipitous—a miner unearthed a violet-zoned gemstone, and it was later identified as a new variety of columbite by Georg von Boesher. By 1968, tanzanite was officially marketed as a December birthstone and quickly became popular for its rich purple, blue, and violet hues.
Tanzanite is unique in that it exhibits trichroism, meaning it shows three different colors when viewed from different angles. This characteristic makes it a visually dynamic gemstone that is often featured in cocktail rings, pendants, and earrings.
Turquoise: A Stone of Protection and Healing
Turquoise is one of the oldest known gemstones, with use dating back to ancient Egypt, China, and the Americas. Its name comes from the French turquoise, meaning “Turkish”, as it was historically traded through Turkey. Turquoise is revered for its healing properties, protection, and spiritual significance across many cultures.
In Native American cultures, turquoise is considered a sacred stone, often used in ceremonial jewelry and amulets. Its blue-green color symbolizes life, health, and divine connection. The metaphysical properties of turquoise include calming emotions, enhancing communication, and promoting inner peace.
Lapis Lazuli and Blue Zircon: Traditional and Modern Gems
Lapis lazuli, with its vibrant blue and golden flecks, has been used since ancient times in jewelry, carvings, and even as a pigment in Egyptian and Mesopotamian art. It is believed to bring wisdom, truth, and prosperity.
Blue zircon, a modern designation, is a rare and brilliant gemstone with high refractive index, giving it a diamond-like sparkle. It is often used in engagement rings and fine jewelry, though its rarity means it is less commonly featured in everyday pieces.
Geological Formation and Sources
Blue Topaz: From Brazil to Swiss Treatment
Natural topaz is a silicate mineral with the chemical formula Al₂SiO₆. It is found in granitic rocks and pegmatites, particularly in Brazil, Mexico, and the United States. However, the blue coloration is not naturally occurring in topaz—most blue topaz is heat-treated and irradiated to achieve the desired hue.
Swiss blue topaz, a term often used in the jewelry industry, refers to topaz that has been treated in Switzerland, a hub for gemstone enhancement. This process transforms the gem into a deep blue or cobalt blue, making it a popular choice for December birthstone jewelry.
Tanzanite: A Geographical and Geological Rarity
Tanzanite is exclusive to Tanzania, found only in the Merelani Hills near Arusha. It is formed in metamorphic rocks under high pressure and temperature, with its violet-blue coloration resulting from traces of vanadium and radiation exposure. Its limited geographic source makes it a rare and valuable gemstone, and its market value can vary depending on the intensity of its color.
Turquoise: From the Earth to the Earrings
Turquoise is a phosphate mineral with the chemical formula CuAl₆(PO₄)₄(OH)₈·4H₂O. It forms in arid environments, often in cavities of volcanic rocks or in sedimentary deposits. Major sources include Nevada (USA), Iran, and China.
The color of turquoise can vary from deep green to bright blue, depending on the proportions of copper and aluminum. Matrix patterns, which are the black or brown veins in the stone, are considered aesthetic features, not flaws.
Lapis Lazuli and Blue Zircon
Lapis lazuli is a metamorphic rock composed mainly of lazurite, with pyrite and calcite often present. It is found in Afghanistan, Chile, and Russia, with Afghanistan being the primary source for the finest quality.
Blue zircon is a zirconium silicate that occurs in metamorphic and igneous rocks. It is found in Madagascar, Thailand, and Australia. Its high refractive index and dispersion make it an excellent diamond simulant, though it is less commonly used in everyday jewelry.
Gemological Properties
| Gemstone | Color | Hardness (Mohs) | Chemical Formula | Refractive Index (RI) | Common Sources |
|---|---|---|---|---|---|
| Blue Topaz | Blue, blue-green | 8 | Al₂SiO₆ | 1.62–1.64 | Brazil, Mexico, Switzerland |
| Tanzanite | Violet, blue, purple | 6–7 | Ca₂Al₃(SiO₄)₃(OH) | 1.69–1.70 | Tanzania |
| Turquoise | Blue-green | 5–6 | CuAl₆(PO₄)₄(OH)₈·4H₂O | 1.61–1.63 | Nevada (USA), Iran, China |
| Lapis Lazuli | Blue, with golden flecks | 5–6 | Lazurite (Na,Ca)₈(Al,Si)₆O₂₀(S,S)₄ | 1.60–1.68 | Afghanistan, Chile, Russia |
| Blue Zircon | Blue | 7–7.5 | ZrSiO₄ | 1.92–2.00 | Madagascar, Thailand, Australia |
Blue Topaz
- Color: Blue, blue-green; coloration is enhanced via heat and irradiation.
- Hardness: 8 on the Mohs scale, making it very durable.
- Clarity: Generally transparent to slightly included, though inclusions are often not visible to the naked eye.
- Cut: Popular cuts include round, oval, princess, and radiant.
- Carat Weight: Available in a wide range, with larger stones often used in centerpieces.
Tanzanite
- Color: Violet, blue, and purple, with trichroism.
- Hardness: 6–7 on the Mohs scale, which is moderately durable.
- Clarity: Often included, with inclusions ranging from visible to hidden.
- Cut: Oval, cushion, and radiant cuts are popular for highlighting its color.
- Carat Weight: Available in larger sizes, though high-quality tanzanite is rare.
Turquoise
- Color: Blue-green with matrix patterns.
- Hardness: 5–6 on the Mohs scale, which is relatively soft.
- Clarity: Opaque, often with matrix inclusions considered aesthetic.
- Cut: Popular in cabochon for pendants and earrings.
- Carat Weight: Available in small to medium sizes, with larger pieces often used in cabochon form.
Lapis Lazuli and Blue Zircon
- Lapis Lazuli is opaque with golden flecks and is often used in cabochon form.
- Blue Zircon has a high refractive index, giving it a sparkling appearance, and is often used as a diamond simulant.
Symbolism and Metaphysical Beliefs
Blue Topaz: Clarity and Inner Strength
Blue topaz is believed to enhance mental clarity, reduce stress, and promote calmness. In ancient times, it was used to ward off curses and protect against poison. It is also associated with loyalty and love, making it a fitting gemstone for engagement rings and friendship gifts.
Tanzanite: Transformation and Intuition
Tanzanite is linked to emotional healing, intuition, and spiritual transformation. Its trichroism is seen as a symbol of seeing life from multiple perspectives. In modern metaphysical practices, tanzanite is used to open the heart and throat chakras, encouraging emotional balance and clear communication.
Turquoise: Protection and Harmony
Turquoise has long been revered as a stone of protection, especially in Native American and Middle Eastern cultures. It is believed to ward off evil, promote healing, and enhance communication. It is also used in ceremonial jewelry and amulets to connect with spiritual guides.
Lapis Lazuli: Wisdom and Truth
Lapis lazuli is a stone of wisdom, truth, and enlightenment. It is believed to enhance intellectual abilities, foster self-awareness, and promote inner truth. In ancient Egypt, it was used in jewelry and cosmetics, symbolizing divine beauty and power.
Blue Zircon: Clarity and Prosperity
Blue zircon is often associated with clarity of thought, prosperity, and protection. It is believed to bring good luck and attract abundance, making it a popular gemstone for new ventures and personal goals.
Care and Cleaning of December Birthstones
Blue Topaz
- Hardness: 8, so it is very durable and can be worn daily.
- Cleaning: Clean with warm water and mild soap. Avoid steam and ultrasonic cleaners, as they may damage the setting or gemstone.
- Storage: Store in a soft cloth or separate compartment to avoid scratches.
Tanzanite
- Hardness: 6–7, so it is moderately durable.
- Cleaning: Clean with warm water and mild soap. Avoid steam and ultrasonic cleaners.
- Storage: Store in a soft pouch or jewelry box to prevent scratches.
Turquoise
- Hardness: 5–6, so it is relatively soft and requires gentle handling.
- Cleaning: Clean with warm water and mild soap. Avoid steam and ultrasonic cleaners, as they may damage the stone.
- Storage: Avoid direct sunlight and chemical exposure (e.g., perfumes, lotions). Store in a cool, dry place.
Lapis Lazuli
- Hardness: 5–6, so it is relatively soft.
- Cleaning: Clean with warm water and mild soap. Avoid steam and ultrasonic cleaners.
- Storage: Store in a soft pouch or compartment to prevent scratches.
Blue Zircon
- Hardness: 7–7.5, making it very durable.
- Cleaning: Clean with warm water and mild soap. Avoid steam and ultrasonic cleaners.
- Storage: Store in a soft pouch or compartment to prevent scratches.
December Birthstone Jewelry: From Rings to Earrings
December birthstone jewelry is diverse and elegant, with blue topaz, tanzanite, and turquoise being the most popular choices. These gems are often set in white gold, yellow gold, or rose gold, and frequently paired with diamonds to enhance their brilliance.
Blue Topaz Rings
Blue topaz rings are a popular choice for December birthdays and holidays. They are often set in white gold or platinum and paired with small diamond accents to create a sparkling effect. These rings can be elegant solitaires, halo settings, or three-stone designs.
Tanzanite Earrings and Pendants
Tanzanite is a favorite for earrings and pendants, particularly in vintage and modern designs. Its rich color and trichroism make it a visually striking gemstone, perfect for holiday parties or special occasions.
Turquoise Jewelry
Turquoise is often used in cabochon form, especially in vintage and Native American-inspired jewelry. It is commonly found in earrings, pendants, and bracelets, and is especially popular in minimalist and bohemian styles.
Conclusion
December birthstones are a celebration of color, history, and symbolism. From the icy brilliance of blue topaz to the rich violet of tanzanite, and from the protective power of turquoise to the rare sparkle of blue zircon, each gemstone tells a unique story. These stones have been revered across cultures and eras, and their beauty and meaning continue to inspire jewelry designers and gemstone lovers around the world.
Whether you are celebrating a December birthday, a holiday, or a special gift, a December birthstone piece makes a meaningful and elegant choice. With proper care and appreciation, these gems can be passed down through generations, preserving their beauty and significance for years to come.