Topaz
Topaz is a rare silicate mineral that occurs in pegmatites, high-temperature quartz veins, and in cavities in granites and rhyolites. Topaz occurs in a wide range of colors. The most valuable colors are natural pink, orange, red, purple and blue. Colorless topaz is the most common; trace elements often make Topaz pale blue or golden brown to yellow orange. Topaz is commonly treated with heat or radiation to make it a deep blue, reddish-orange, pale green, pink, or purple. Topaz is found in countries all over the globe with some of the largest specimens originating from Minas Gerais, Brazil. It is the hardest silicate mineral and one of the hardest naturally occurring minerals on planet Earth.