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Barium chloride sulfate is precipitated as coarse crystalline barium sulfate. The precipitate is determined gravimetrically:

SO₄^2- + Ba²⁺ → BaSO₄
 

A water sample is run through an ion exchanger in which all of the cations are replaced with hydrogen ions. The sulfate is determined through titration in the presence of a previously prepared barium chloride solution, of which a known amount in excess of that required is added in advance. The quantity is measured by complexometric titration. The difference between the initial concentration of barium chloride and the amount determined by back titration corresponds to the sulfate content.

In many cases, particularly at higher contents, an alternative and sufficiently accurate measurement is possible, called the “negative m value” or the “total mineral acid value” (without carbonic acid). This is achieved through titration. Subsequently, the mval values for the anions (Cl^-, NO₃^-, NO₂^-, PO₄^3-) are subtracted from the result.

In the presence of barium chloride, sulfate ions form barium sulfate, which is only slightly soluble in water. The turbidity produced by doing so is determined with a photometer.

The sample is extracted with petroleum ether in a Soxhlet apparatus equipped with a reflux condenser; the solvent is evaporated and the crude fat residue weighed.

Oils and fats dispersed in water are precipitated using aluminum sulfate. After dissolving the precipitate with hydrochloric acid in organic solvents, they can be separated from the mineral salts.