{i} state of being concrete; act of concreting; hard inorganic mass formed in the body
A rounded mass or nodule produced by an aggregation of the material around a center; as, the calcareous concretions common in beds of clay
A local concentration of chemical compounds (e g calcium carbonate, iron oxide) in the form of a grain or nodule of varying size, shape, hardness, and color Concretions of significance in hydric soils are usually iron and/or manganese oxides occurring at or near the soil surface, which develop under conditions of prolonged soil saturation
A mass of mineral matter, often rounded, found in sedimentary rock It is harder than its surrounding rock
A hard round, oval, or other-shaped of mass of mineral or aggregate matter of varying sizes Commonly forms by chemical precipitation around a nucleus or center, or replacement of precursor organic or inorganic material An example is siderite (iron, calcium carbonate) concretions
Spherical to elliptical nodules, harder than the surrounding rock, formed by accumulation of mineral matter (example - iron oxide) after deposition of sedimentary rock