The government today hiked export duty on iron ore lumps by 5 per cent to 15 per cent to discourage its shipments and cool down the prevailing prices of the vital input for making steel. The export duty on iron ore fines would remain unchanged at five per cent,Revenue Secretary Sunil Mitra told reporters here. Export duty on iron ore lumps has been increased to 15 per cent from 10 per cent, Mitra said. Mitra further said that customs duty on stainless steel scrap - used mainly in making the alloy- has been cut to 2.5 per cent from five per cent. The duty hike on iron ore lumps,primarily used by domestic producers to make steel,would help in cooling its prices which has increased by about 90 per cent and is hovering in the range of USD 120-160 per tonne as against year-ago period. The move may help bring down the input cost pressure on steel companies and could lead to reduction in prices of steel,industry observers said. In 2008-09,iron ore exports amounted to 106 million tonnes,about 85 per cent of which were fines.