'Lime' 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
limestone products,
concrete and
mortar) and as
chemical feedstocks, among other uses. Lime 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
limestone 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 lime'' or ''hydrated lime'' (
calcium hydroxide, Ca(OH)
2), the process of which is called ''slaking of lime''.
When the term is encountered in an agricultural context, it probably refers to
agricultural lime. Otherwise it most commonly means
slaked lime, as the more dangerous form is usually described more specifically as
quicklime or ''burnt lime''.
External links
★
The National Lime Association (US & Canada)
★
European Lime Association
★
Carmeuse Group - Lime producer
See also
★
calcium hydroxide
★
gypsum: a similar mineral.
★
sascab: a building and paving material (
Central America).
★
hydraulic lime