Topaz is a silicate mineral composed of aluminum and fluorine, represented by the chemical formula Al2SiO4(F, OH)2. It is commonly utilized as a gemstone in jewelry and decorative items. While natural topaz is typically colorless, impurities can impart hues ranging from pale blue to golden brown or yellow-orange. Treatments involving heat or radiation can enhance its color to deep blue, reddish-orange, pale green, pink, or purple.
As a nesosilicate and aluminosilicate mineral, topaz ranks among the hardest naturally occurring minerals and features a low index of refraction. It crystallizes in the orthorhombic system and exhibits a dipyramidal crystal class. Topaz is found in various global locations, with Brazil and Russia being notable sources, and is often extracted through open-pit or alluvial mining methods.
The term "topaz" is thought to originate from the Greek word Τοπάζιος (Topázios) or Τοπάζιον (Topázion), linked to St. John's Island in the Red Sea, where a yellow stone was historically mined. The mineral was first named "topaz" in 1737. Ancient Sri Lanka also played a role in the trade of topazes to Greece and Egypt, contributing to the etymology of the name. Some sources suggest a connection to the Sanskrit word तपस् (tapas), meaning "heat" or "fire."
