Oliver Manufacturing Company density separators destoner OLIVER MANUFACTURING COMPANY Since its inception, Oliver Manufacturing Company has solved the world's separation problems by supplying gravity separators and stoners of the highest value. We have earned a worldwide reputation for superior service to, and warm respect for, our customers. Doing business with integrity is an uncompromising attitude of always providing customers with quality machines and value added services that assure their business success.Today, Oliver Manufacturing Company maintains an experienced staff exclusively focused on solving your dry separation problems with advanced fluidized bed technology.