A Clay is a fine grained sediment made through a natural basic geological process. Either by: 1) the weathering of bedrock; or 2) the deposition of fine grained sediments in water. A clay particle should measure less than 0.005 millimeters in diameter. Oher sources say; with a particle size of less than two-thousandths of a millimeter. Clay has the property of plasticity when wet.
See also: Clay matrix, Clay temper, Porcelain clay, Porcelain paste.
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