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About ClayHide

As a Commodity:
A clay-grade clastic-sediment, extremely common on the earth's surface.

Clay is a fine-grained natural sediment, soil or rock component that comprises mostly one or more clay minerals or clays (hydrous phyllosilicates: mostly smectite, illite, chlorite and kandite) normally with trace to major amounts of quartz, iron and aluminium oxy-hydroxides (mostly goethite and gibbsite) and organic matter.

Clays are soft and plastic when wet due to the platy particle shape and fine size and become hard, brittle and non–plastic upon drying. Clays are white or pale coloured when pure but appear in various colours from grey to black, green, yellow, brown or red when impure.

Clays are usually distinguished by geologists or pedologists from other fine-grained soils and sediments by their grain size and/or mineralogy, though geotechnical engineers distinguish them by plasticity. Silts, which are fine-grained soils and sediments that are not normally dominated by clay minerals, have larger particle sizes than clays. Geologists usually consider the division to occur at a particle size of 2 µm, sedimentologists often use 4–5 μm, and colloid chemists use 1 μm. Geotechnical engineers distinguish between silts and clays based on the plasticity properties of the soil, as measured by the soils' Atterberg limits. ISO 14688 grades clay particles as being smaller than 2 μm and silt particles as being larger.

Classification of ClayHide

Sub-divisions of ClayHide

Pronounciation of ClayHide

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Jolyon & Katya RalphUnited Kingdom

Synonyms of ClayHide

References for ClayHide

Reference List:
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Le Châtelier, H. (1887) De l'action de la chaleur sur les argiles. Bulletin de la Société française de Minéralogie, 10, 204.
Wilson, M.J. (1999) The origin and formation of clay minerals in soils: past, present and future perspectives. Clay Mineralogy, 34, 7-24.
Owliaie, H.R., Abtahi, A., Heck, R.J. (2005) Pedogenesis and clay mineralogical investigation of soils formed on gypsiferous and calcareous materials, on a transect, southwestern Iran. Geoderma, 134, 62-81.
Mirkhani, R., Roozitalab, M.H., Khaleghpanah, N., Rezaei, N., Teimouri, S. (2010) Physico-chemical characteristics and clay mineralogy composition of selected soils in arid and semiarid regions of Iran. Extended Abstracts – 21st Australian Clay Minerals Conference – Brisbane, August 2010, 151-154.

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