TOKYO : Nippon Steel, the world's No.4 steelmaker, will keep on hunting for stakes in coking coal and iron ore mines to ensure a stable supply of essential raw materials and mitigate the potential impact of price volatility, its executive said. A Glencore-led consortium, including Nippon Steel, sealed one of the mining sector's biggest deals in years this month, agreeing to buy Canadian miner Teck Resources' steelmaking coal unit for $9 billion. The Japanese company will pay around $1.34 billion for a 20 per cent stake.