Lithium sulfate is a white inorganic salt used to treat bipolar disorder (see Lithium pharmacology). It is soluble in water, though it does not follow the usual trend of solubility versus temperature - its solubility in water decreases with increasing temperature. This property is shared with few inorganic compounds, such as the lanthanide sulfates.

Aluminium sulfate, written as Al2(SO4)3 or Al2O12S3, is a widely used industrial chemical. It is sometimes incorrectly referred to as alum, as it is closely related to this group of compounds. It occurs naturally as the mineral alunogenite. It is frequently used as a flocculating agent in the purification of drinking water[1][2] and waste water treatment plants, and also in paper manufacturing.

Aluminium sulfate is rarely, if ever, encountered as the anhydrous salt. It forms a number of different hydrates, of which the hexadecahydrate Al2(SO4)3o16H2O and octadecahydrate Al2(SO4)3o18H2O are the most common.

Ammonium sulfate is prepared commercially by reacting ammonia with sulfuric acid (H2SO4). Ammonium sulfate is prepared commercially from the ammoniacal liquor of gas-works and is purified by recrystallisation. It forms large rhombic prisms, has a somewhat saline taste and is easily soluble in water. The aqueous solution on boiling loses some ammonia and forms an acid sulfate.

Barium sulfate is frequently used clinically as a radiocontrast agent for X-ray imaging and other diagnostic procedures. It is most often used in imaging of the GI tract during what is colloquially known as a 'Barium meal'.

It is administered, orally or by enema, as a suspension of fine particles in an aqueous solution (often with sweetening agents added). Although barium is a heavy metal, and its water-soluble compounds are often highly toxic, the extremely low solubility of barium sulfate protects the patient from absorbing harmful amounts of the metal. Barium sulfate is also readily removed from the body, unlike Thorotrast, which it replaced. Due to the relatively high atomic number (Z = 56) of barium, its compounds absorb X-rays more strongly than compounds derived from lighter nuclei.