stannous fluoride
Stannous fluoride (SnF2) is a fluoride of tin, and it is a colorless solid at normal temperature and pressure.
Stannous fluoride is a white monoclinic crystal. It has a boiling point of 850℃ and is soluble in cold water and hydrofluoric acid.
Stannous fluoride can be used in toothpaste production to protect teeth from calcium dissolution.