
From the blue to bluish purple of tanzanite, to the intense blue and green of turquoise, to the rainbow varieties of zircon – there’s a color for everyone.
If blue is what you’re looking for, all three December birthstones have their own unique take on this favorite hue.
Tanzanite
The tanzanite birthstone is often described as “velvety,” mostly because of its deep and saturated color, which ranges from a pure rich blue to violet, with the blue considered most valuable.
Tanzanite is also the gemstone for the 24th wedding anniversary.
This December birthstone (6 to 7 on the Mohs scale of harness) is resistant to the effects of normal heat, light and common chemicals. Still, the December birthstone may crack if exposed to very high temperatures or sudden temperature changes, and it abrades easily.
Warm, soapy water is the best way to clean this December birthstone.
Turquoise
Turquoise is a semi-translucent to opaque gem that ranges from blue to green and often has veins of matrix (remnants of the rock in which it formed) running through it.
This December birthstone has been cherished for millennia. The pharaohs and other rulers of ancient Egypt adorned themselves with it. Chinese artisans carved it more than 3,000 years ago.
Although New Mexico was the largest producer of turquoise in the U.S. until the 1920s, today most of the U.S. production of this December birthstone comes from Arizona and Nevada.
Some turquoise is treated to improve its durability (it has a Mohs hardness of 5 to 6), appearance and polish. Turquoise can be dyed or chemically enhanced by adding an epoxy or acrylic resin for greater hardness or better color. Also seen are cavities filled with a metal-loaded epoxy to imitate pyrite inclusions.
Your turquoise birthstone can be damaged by acids, and it can be discolored by certain chemicals, cosmetics and even skin oils or perspiration. It’s safe to clean turquoise jewelry with warm, soapy water, but this December birthstone should never be cleaned with steam or ultrasonic cleaners.
Zircon
The origins of the word “zircon” have elicited colorful debate. Some scholars believe it comes from the Arabic word zarkun, meaning “cinnabar” or “vermilion.” Others think the source is the Persian word zargun, or “gold colored.” Considering the broad color palette for this December birthstone – red, orange, yellow, brown, green and blue – either derivation seems possible. Colorless zircon is known for its brilliance and flashes of multicolored light, called fire, which have resulted in centuries of confusion with diamond.
This December birthstone is often located near sapphire sources. In addition to Sri Lanka and Australia, countries where the two gems overlap include Myanmar, Vietnam and Cambodia.
Zircon ranges from 6 to 7.5 on the Mohs scale of hardness. It is commonly heat treated to produce blue and colorless varieties, as well as orange, yellow and red.
Because zircon tends to abrade, it is best to avoid wearing it in rough conditions, such as while gardening, playing sports or doing dishes.
Clean your zircon using a soft brush and mild soap in warm water. Ultrasonic and steam cleaners are not recommended for this December birthstone.