As the main ions due to which the dry residue can be determined, there are: sulfates, chlorides, carbonates, nitrates, bicarbonates. There is their subdivision into organic and mineral residues, which differ in their boiling points. A dry residue means the presence of dissolved, non-volatile solids in water.

Weak mineralised water, that contains up to 50 mg/l of dry residue (the total quantity of mineral present in water). Weak mineralised or olligometallic water, if it contains up to 500 mg/l of dry residue. Medium mineralised water that contains from 500 mg/l to 1500 mg/l of dry residue.

Dry matter is measured in the laboratory. A weighed sample of the substance mixture (sometimes called fresh mass) is taken and heated to over 100°C in the drying room in order to evaporate the residual moisture (mostly water). The remaining dry residue is weighed and proportioned. This yields the dry substance content of the mixture.