December Birthstones: Turquoise & Tanzanite
Turquoise comes from the French name for “Turkish stone” as it was known to traders in medieval times. It was one of the most popular gems from the beginning of recorded history – a favorite of Egyptian pharoahs and Aztec emperors alike.
Turquoise forms in many of the world’s desert regions, in copper deposits where water has moved through aluminous rock. During this chemical reaction, minerals give it its characteristic color and veining. The more iron and aluminum it contains, the greener the color of the turquoise, while higher copper content results in a stronger blue color that is most desirable.
Turquoise jewelry is highly versatile in its design potential and easy to wear if it receives proper care. Avoid exposure to chemicals and oils, and store safely where it won’t be scratched by harder gems.
Bright blue Persian turquoise has long been considered some of the world’s finest. Image: irpedia.com
This newest addition to the birthstone array was discovered in the 1960s, named for the African nation of Tanzania where it is found in the foothills of Kilimanjaro. Its alluring, exotic color has made it increasingly popular ever since and in 2002, AGTA made it an official December birthstone.
Tanzanite is a form of the mineral zoisite that can appear to change color, ranging from deep blue to purplish pink depending on the lighting. Most jewelry-grade gems are heat-treated to preserve their color and enhance their clarity.
Tanzanite is a softer gem most commonly used in pendants and earrings to prevent accidental damage. It is suitable for everyday wear, but protect it from sharp impact and extreme temperatures, and clean gently – never use ultrasonic cleaners.
Near-colorless topaz will turn brilliant sky blue when its molecules are bombarded with electrons. It’s become one of the most beloved of December’s elegant blue birthstones. Find out more on the Gem Encyclopedia →
Read more about December birthstones:
EarthSky.org: Turquoise & Zircon