Mortar is a binder used between blocks or bricks or to coat ceilings and walls. Mortar is produced by mixing lime, pozzolan, or (Portland) cement with sand or gravel and appropriate amounts of water. The hydraulic reaction of water and lime or cement determines the characteristics of the binder, such as strength and other binding properties.
Cf., Portland cement, cement

See hydrotalcite group.

See hydrotalcite group.

Indicates a soil composite that is largely organic in nature, lacks recognizable plant structures and is very darkly colored. It differs from peat in being darker, lacking plant structures and having increased mineral content. It differs from ball clay in having significantly higher organic content and in being much darker.

Soft, plastic, sticky or slippery matter, generally containing water and clay minerals derived from fine-grained soil/regolith/sediment materials. Mud is commonly composed of clay-size particles, but often contains mixtures of sand- and silt-size particles as well as microorganisms. Potter et al. (2005) considers mud a sedimentological field term for unconsolidated fine-grained sediments of any composition and consisting of 50% or more of particles smaller than 0.0063 mm (i.e., clay and silt size fractions).
Cf., see geotherapy, matured mud, pelotherapy, poultice, Udden-Wentworth scale

Therapeutic use of healing mud (hydrated clay) in an empirical way and without medical supervision for palliative or cosmetic purposes. Traditionally, mud therapy was practiced in the natural environment where the mud occurs, but this is no longer the case.
See aesthetic medicine, antibacterial clay, geotherapy, healing clay, pelotherapy, peloid

An indurated, sedimeantary clay-bearing rock with 33-65% clay-size constituents and stratification of >10 mm thickness (bedding). An individual mudrock bed may be internally massive (after Potter et al., 2005).
See clayshale, claystone, mud, mudstone, mudshale, silt, siltstone.

An indurated, sedimentary clay-bearing rock with 33-65% clay-size constituents and lamination (stratification of <10 mm thickness), after Potter et al. (2005). See clay, clayshale, claystone, mud, mudstone, mudrock, silt, siltstone.

A general term for a rock which is similar to shale but used to describe a clay-rich rock without laminations. The fraction of clay and/or silt components are not well defined. The silt component may be of major proportions.
See clay, clayshale, claystone, mud, mudrock, mudshale, silt, siltstone.

In soil science, mull is a type of humus of the A horizon, without distinct layering, and composed of organic matter intimately mixed with the fine-grained mineral fraction.
Syn., mull humus