Term: milling (grinding)
https://doi.org/10.1351/goldbook.M03928

Definition:
The mechanical reduction of the particle size of a sample by attribution (friction), impact or cutting. The required particle size of a sample is related to the size of the test portion and the number of particles required to ensure homogeneity among test portions. The reduction in particle size may sometimes result in particles of different hardness and density, which produces inhomogeneity during the preparation of the test sample or during the withdrawal of the test portion.

Related Terms:
1) test portion (http://doi.org/10.1351/goldbook.T06284).
2) test sample (http://doi.org/10.1351/goldbook.T06285).

Source: PAC, 1990, 62, 1193. 'Nomenclature for sampling in analytical chemistry (Recommendations 1990)' on page 1205 (https://doi.org/10.1351/pac199062061193)

Citation: 'milling (grinding)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03928

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