LIMESTONE CONSUMPTION FACTOR (LCF):- LCF studies are crucial for rationalization of limestone consumption in production of cement, estimating royalty payable to state for the limestone mined from their respective captive mines internal material audit of the concerned cement plants. Around 200 Limestone Consumption Factor (LCF) studies have been performed by NCB for cement plants from all over the country. During the year 2018, LCF studies were completed for 18 cement plants.