Strontium sulfate (SrSO
4) is the
sulfate salt of
strontium. It is a white crystalline powder and occurs in nature as the mineral
celestine. It is poorly soluble in water to the extent of 1 part in 8,800. It is more soluble in dilute
HCl and
nitric acid and appreciably soluble in alkali
chloride solutions (e.g.
sodium chloride).