<unk> is a general term for various naturally occurring minerals and materials derived from them, in which carbonates, oxides and hydroxides of calcium predominate.
These materials are used in large quantities as building and engineering materials (including<unk> tone products, concrete and mortar) and as chemical feedstocks, among other uses.<unk> industries and the use of many of the resulting products date from prehistoric periods in both the Old World and the New World.
The rocks and minerals from which these materials are derived, typically<unk> tone or chalk, are composed primarily of calcium carbonate. They may be cut, crushed or pulverized and chemically altered.  "Burning" (calcination) converts them into the highly caustic material quicklime (calcium oxide, CaO) and, through subsequent addition of water, into the less caustic (but still strongly alkaline) slaked<unk> or hydrated<unk> (calcium hydroxide, Ca(OH)2), the process of which is called slaking of<unk> 
When the term is encountered in an agricultural context, it probably refers to  agricultural<unk>  Otherwise it most commonly means slaked<unk>  as the more dangerous form is usually described more specifically as quicklime or burnt<unk>
Lime 
Tic
Acyl
Oxamyl
Carbide
Awe 
Sole 
Sultiame