The rock comprising of clay mixture in the rate of 30-50% and limestone mixture in the rate of 50-70% of limestone and clay in the nature is called as marn. It contains silica, clay materials and iron oxide.
Cement clinker is obtained by firing raw material mixture of limestone and clay at high temperatures. Since marn has this mixture naturally or has characteristics very close to this compound, it is the ideal cement raw material. Moreover, it is softer than the limestone and therefore it is ground easily and energy consumption during crushing-grinding is low.
Marn, that Goltas Cimento A.S needs is supplied from marn quarries at about 3 km distance in the North-west of the plant.