Limestone

Description

Limestone is a sedimentary rock composed predominantly of calcium carbonate, primarily existing in the crystalline mineral forms of calcite and aragonite. It originates from marine environments, where it accumulates through the precipitation of calcium from water, either via inorganic processes or the biological accumulation of skeletal fragments like shells and coral. Geologically, limestone displays diverse textures, ranging from granular and clastic to massive or fossiliferous structures, including varieties such as travertine, chalk, and oolitic limestone. In industrial and ceramic contexts, a material is classified as limestone when it contains at least 50% calcium oxide (CaO). Often referred to as whiting or ground calcium carbonate (GCC) in ceramic applications, this material serves as a primary source of CaO for the formulation of glazes and frits. Historically, the thermal decomposition of limestone to produce calcium oxide—a process that facilitates the creation of mortar and cement—represents a foundational chemical application of the mineral. Manufacturers typically process raw limestone into standardized, refined powders to ensure chemical consistency and minimal impurity levels.