... stone mill grinder is the equipment specializing in producing fine and superfine powder of non-inflammable, non-explosive and ... and vermiculite, sepiolite, attapulgite, rectorite, diatomite, barite, gypsum, alunite, graphite, fluorite, rock phosphate, kalium ore, pumice, etc., totally more than ... valve at the bottom; a small proportion of the fine powders, with airflow, moves to the dust cleaner, ...