Country's largest iron ore producer NMDC has increased the price of high grade iron ore (lumps) by Rs 400 to Rs 3,000 per tonne. The state-run firm has also hiked the price of iron ore fines, which are inferior grade ore, by Rs 400 to Rs 2,760 per tonne. The revised prices exclude royalty, DMF (District Mineral Fund), NMET (National Mineral Exploration Trust), cess, forest permit fee and other taxes, NMDC said in a BSE filing. This is the second price revision done by the company in a month. The last revision was done earlier on February 2 when the company had fixed the rates of lump ore at Rs 2,600 per tonne and that of fines at Rs 2,360 per tonne. Iron ore is the main ingredient used in making steel.