Antimony trioxide (Sb₂O₃) is a white crystalline powder that is the most commercially significant compound of antimony. It is primarily used as a flame retardant in various materials, including plastics, textiles, and coatings. This compound is produced by roasting antimony ores or by oxidizing antimony metal. Antimony trioxide has a high melting point of 656°C and a boiling point of 1,425°C, making it stable under high temperatures. It is insoluble in water but can dissolve in acids and strong bases. In addition to its flame-retardant properties, antimony trioxide is used as a catalyst in the production of polyethylene terephthalate (PET) and as an opacifying agent in glasses, ceramics, and enamels. Despite its widespread use, antimony trioxide poses health risks, including respiratory issues and potential carcinogenic effects, necessitating careful handling and adherence to safety guidelines. The compound’s production and application continue to evolve, with ongoing research aimed at improving its efficiency and reducing its environmental impact. As industries seek safer and more sustainable alternatives, the role of antimony trioxide in manufacturing and safety applications remains a critical area of study.