Existing rules forbid captive miners from selling rejects, sub-grade or low-grade ores that are not usable for downstream processes. : Captive mine lessees have sought approval to sell inferior grades of minerals, saying it will reduce waste at mines. Their demand stems from the fact that baser grade ore could not be used in the mother plants or the downstream units. Such lower grade ore and rejects can be disposed off to other industries where they find applications.