CLAY n.
on consisting of the oxide or carbonate of iron mixed with clay or sand. -- Clay marl, a whitish, smooth, chalky clay. -- Clay mill, a mill for mixing and tempering clay; a pug mill. -- Clay pit, a pit where clay is dug. -- Clay slate (Min.), argillaceous schist; argillite. -- Fatty clays, clays having a greasy fe…
COQUINA n.
A soft, whitish, coral-like stone, formed of broken shells and corals, found in the southern United States, and used for roadbeds and for building material, as in the fort at St. Augustine, Florida.