What Is Calcination Residue? How It Relates to Residue on

Calcination residue is simply another way of saying residue on ignition. Both mean burning a sample down to the inorganic ash that will not burn away. The only difference is wording: residue on ignition is the formal pharmacopeial term, while calcination is more colloquial.

If you see calcination residue in a document, treat it exactly as residue on ignition, the method, temperature (700–800 °C) and constant-weight criterion (0.3 mg) are identical.

Relation to residue on ignition

They share the same principle: char, high-temperature ignition, constant weight, weigh residue. Standards such as ChP 0841 and USP 733 uniformly use residue on ignition; instruments like the LabStone IRT-A are also named accordingly.