Also called slaked lime, lime hydrated is calcium carbonate (limestone) that has been crushed, burned, and mixed with water. The limestone is extracted from mines and quarries before being calcined at temperatures approaching 1000 degrees Celsius in kilns to produce what is known as quicklime, which is a highly caustic powdery substance often used in concrete construction and agriculture. The quicklime is then hydrated, or mixed with water in a process called slaking, which produces hydrated or slaked lime. Lime hydrated has literally hundreds of applications in industrial and construction settings, from refining sugar to creating various consistencies, setting times, and formulations of nearly every form of concrete. It is also used extensively in creating plaster and drywall compounds, as well as in agricultural settings to alter soil quality. An essential building additive for millennia, lime hydrated is an essential compound needed to create virtually every type of reinforced industrial and commercial structure.