blue to·paz | ˈblü ˈtō-ˌpaz
A topaz that is light brown or colorless when mined, which turns a vivid blue when exposed to heat
Today, blue is the most popular topaz used in jewelry. Therefore, there are several jewelry pieces on the market containing the blue topaz gemstone. An attractive, yet inexpensive gemstone, blue topaz is rare in nature. In fact, prior to the 1970s, most topazes were brown. However, today blue topaz is widely available due to gemstone treatment processes. Turning colorless topazes into blue topazes began in the 1970s when gemologists began treating these stones with high-energy electron or gamma radiation. This practice heated up the colorless topazes into beautiful shades of blue. The two most popular variants of blue topaz are the Swiss Blue, which is bright and has a light tone and light to moderate color saturation, and the London Blue, which is dark blue topaz with moderate to dark color and saturation. Proper care for blue topaz includes using warm soap and water. You should avoid using steam or ultrasonic steaming on these gemstones.