04841 IUPAC Gold Book - primary sample 10.1351/goldbook.P04841 P04841 current 1 The collection of one or more increments or units initially taken from a population. The portions may be either combined (composited or bulked sample) or kept separate (gross sample). If combined and mixed to homogeneity, it is a blended bulk sample. The term 'bulk sample' is commonly used in the sampling literature as the sample formed by combining increments. The term is ambiguous since it could also mean a sample from a bulk lot and it does not indicate whether the increments or units are kept separate or combined. Such use should be discouraged because less ambiguous alternative terms (composite sample, aggregate sample) are available. 'Lot sample' and 'batch sample' have also been used for this concept, but they are self limiting terms. The use of 'primary' in this sense is not meant to imply the necessity for multistage sampling. bulk sample https://goldbook.iupac.org//terms/view/B00756 collection https://goldbook.iupac.org//terms/view/C01148 composite sample https://goldbook.iupac.org//terms/view/C01212 multistage sampling https://goldbook.iupac.org//terms/view/M04065 PAC, 1990, 62, 1193. 'Nomenclature for sampling in analytical chemistry (Recommendations 1990)' on page 1205 (https://doi.org/10.1351/pac199062061193) https://goldbook.iupac.org/terms/view/P04841/html https://goldbook.iupac.org/terms/view/P04841/json https://goldbook.iupac.org/terms/view/P04841/plain Citation: 'primary sample' 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.P04841 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. 2026-04-20T23:32:59+00:00