Processed minerals and ores classification defines eligible mineral products and processing methods for tax schedule treatment. Schedule 12 enumerates specific categories of processed minerals and ores covered by the tax schedule-including pulverised minerals, processed bentonite and kaolin, beneficiated concentrates, various mica products, exfoliated and calcined minerals, sized and concentrated iron ores, agglomerated ore, and cut and polished stones-and defines 'processed' by reference to methods such as mechanical dressing to obtain concentrates, pulverisation, calcination, micronisation, agglomeration, cutting and polishing, washing and levigation, mechanical benefication, wet sizing and classification, and other upgrading techniques like chemical impurity removal, gravity separation, bleaching, flotation or filtration.