TOPAZ is a common gemstone that has been prized for centuries for its hardness, clarity, and beauty. Mineral collectors are attracted to its well-formed crystals. Topaz is a silicate mineral of aluminum and fluorine, and is one of the hardest minerals in nature. Crystals have been found in sizes reaching several hundred pounds.
Pure topaz is colorless and transparent; typical topaz is white, yellow, pale gray or reddish-orange, blue brown. Orange topaz, also known as precious topaz, is the traditional November birthstone. Imperial topaz is yellow, pink or pink-orange. Many brown or pale topazes are treated to make them bright yellow, gold, pink or violet colored. Blue topaz rarely occurs naturally, and colorless, gray or pale yellow and blue material is often heat treated and irradiated to produce a darker blue.