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Related to rock flour: Glacial flour
rock flour[′räk ‚flau̇·ər]
A fine, chemically unweathered powder of rock-forming minerals produced by pulverization of rock fragments during natural transport or crushing. Also known as glacial flour.
A very finely powdered rock material; Also see silt.
silt, inorganic silt, rock flour
A granular material that is nonplastic or very slightly plastic and exhibits little or no strength when air-dried; usually has a grain size between 0.002 mm and 0.05 mm in diameter.