The National Commodity and Derivatives Exchange (NCDEX) will launch futures contracts for nickel cathodes, aluminium ingots and zinc ingots from May 22.Looking at the high usage of nickel in the steel industry, the exchange is launching the contract at a size of 250 kg. The exchange has marked Bhiwandi as the base centre and Delhi as an additional delivery centre, the exchange said in a release issued today. The contract size in case of aluminium ingots will be two metric tonne, and Bhiwandi and Delhi are the delivery centres, the release said. In case of zinc ingot contracts, the contract size will be two metric tonne.All the three contracts would be settled on the basis of international prices in rupee denomination, the release said.Sanjay Singhavi, assistant vice-president of NCDEX, said: "The launch of delivery- based futures contracts will give hedgers a genuine platform to hedge their price risks in non-ferrous metals in highly volatile markets."