To manufacture CEM I 42.5 Portland cement,a precisely specified mixture of raw materials containing limestone,marl,
iron ore and bauxide is burned.The produced clinker,together with calcium sulfate to control setting,is then ground to
produce cement of the required fineness.Up to 5% of minor additional constituent (limestone) is incorparated at the
rinding stage. CEM I 42,5 R is made from the same clinker as CEM I 42,5 N but CEM I 42,5 R is more finely ground in
order to promote greater reactivity.Therefore, CEM I 42,5 R delivers higher early strength without significant reduction
of setting time.This type of cement is suitable for applications of prefabricated house , pre-tension concrate,art structures
and cast-tunnel applications which are common at the present day at gross house buildings.