... -11 4.Vermiculite usage :1>.Construction :lightwight material ,light aggregate concrete ,heat-resisting material,wall material,bora firproofing ,fire mortar,fireproofing tile2>.Heat ... tunnel ,wall of public and ceiling3>.Metallurgy :clad material in steel,ironmaking ,foundry,bulk material of vermiculite4>.Horticulture :lawn of golf,seed preservation ...