00180 IUPAC Gold Book - ageing of precipitate 10.1351/goldbook.A00180 A00180 current 1 The time-dependent change of those properties of a precipitate, e.g. loss of water, growth of crystals, recrystallization, decrease of the specific surface, loss of coprecipitated substances, which generally improve the filtering properties. The process of ageing is very often promoted by maintaining the precipitate and precipitation medium together at elevated temperatures for a period of time. The terms chemical, physical and thermal ageing may be used in cases in which some of the (usually combined) effects named above are to be emphasized specifically. precipitation https://goldbook.iupac.org//terms/view/P04795 recrystallization https://goldbook.iupac.org//terms/view/R05208 Orange Book, 2nd ed., p. 86 (https://media.iupac.org/publications/analytical_compendium/) https://goldbook.iupac.org/terms/view/A00180/html https://goldbook.iupac.org/terms/view/A00180/json https://goldbook.iupac.org/terms/view/A00180/plain Citation: 'ageing of precipitate' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.A00180 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-05-12T16:18:25+00:00