(i) Importance of Lime stone—Lime stone is an important primary material and is the cheapest form of alkali.
(a) It is used to prepare Quick lime CaO.
It is used as flux to remove acidic impurities,
(ii) Importance of Cement—Cement is an important building material. It is used in the concrete and reinforced concrete, in plastering and in construction of dams, bridges and buildings.
(iii) Importance of Plaster of Paris—Because of remarkable property of setting with water, Plaster of Paris finds use in building industry and in plasters. It is used for immobilising the affected part of the organ where there is bone fracture or sprain. It is also used in casting of statues and busts.