Columbia Encyclopedia

Search results

305 results found

clay

(Encyclopedia)clay, common name for a number of fine-grained, earthy materials that become plastic when wet. Chemically, clays are hydrous aluminum silicates, ordinarily containing impurities, e.g., potassium, sodi...

fire clay

(Encyclopedia)fire clay, clay that has a high degree of resistance to heat. By the best standards it should have a fusion point higher than 1,600℃. The term “fire clay” is commonly held to exclude kaolin and ...

Clay, Henry

(Encyclopedia)Clay, Henry, 1777–1852, American statesman, b. Hanover co., Va. In 1828, Clay again supported Adams for President, and Jackson's success bitterly disappointed him. Although he intended to retir...

flint clay

(Encyclopedia)flint clay: see fire clay.

Clay, Lucius DuBignon

(Encyclopedia)Clay, Lucius DuBignon dəbĭnˈyən, dübēnyôNˈ [key], 1897–1978, American general, b. Marietta, Ga. A graduate of West Point and an engineering officer, he held many army administrative posts an...

loam

(Encyclopedia)loam, soil composed of sand, silt, clay, and organic matter in evenly mixed particles of various sizes. More fertile than sandy soils, loam is not stiff and tenacious like clay soils. Its porosity all...

bentonite

(Encyclopedia)bentonite bĕnˈtənītˌ [key]: see clay. ...

china clay

(Encyclopedia)china clay, one of the purest of the clays, composed chiefly of the mineral kaolinite usually formed when granite is changed by hydrothermal metamorphism. Usage of the terms china clay and kaolin is n...

clay pan

(Encyclopedia)clay pan: see hardpan.
 

Browse by Subject