Powder
From Online Dictionary of Crystallography
مسحوق (Ar). Poudre (Fr). Pulver (Ge). Polvere (It). 粉末 (Ja). Polvo (Sp).
A powder is defined in EN 1330-11 (British Standards Institution, 2007) as a large number of crystallites and/or particles (i.e. grains, agglomerates or aggregates; crystalline or non-crystalline) irrespective of any adhesion between them and thus can be a loose powder (in the sense of common language), a solid block, a thin film or even a liquid. An ideal powder is represented by a virtually unlimited number of sufficiently sized, randomly oriented and spherical crystallites.
Reference
- British Standards Institution (2007) BS EN 1330-11:2007 Non-destructive testing. Terminology. Terms used in X-ray diffraction from polycrystalline and amorphous materials. London: BSI.