TOPAZ is a beautiful and precious stone, and very rare, so it is mainly used in jewelry. It is a sparkling gemstone that emanates beautiful natural light. Although quite hard, it is too rare to be used as an industrial tool. TOPAZ may be colorless, or appear in a number of different colors. The most valuable varieties are TOPÁZIO XEREZ. which is yellow, and IMPERIAL TOPAZ, which is orange. The most beautiful examples of TOPÁZIO are found in Minas Gerais, Brazil. The largest species ever found weighed over 2 tons. Colorless TOPAZS are very superficially similar to diamonds and are widely used as copies and imitations. The two gems, however, are completely different chemically. Diamond is made of pure carbon, while TOPAZ is an aluminum silicate.