A ball mill, a type of crusher, is a cylindrical device used to grind (or mix) materials like ores, chemicals, ceramics and paints. Ball mills rotate around a horizontal axis, partially filled with the material to be ground plus the grinding medium, mostly stainless steel balls. An internal cascading effect reduces the material to a fine powder. Industrial ball mills can operate continuously, fed at one end and discharged at the other. Large to medium ball mills are mechanically rotated on their axis, but small ones normally consist of a cylindrical capped container that sits on two drive shafts (pulleys and belts are used to transmit rotary motion). A rock tumbler is a similar device. Ball mills are also used in pyrotechnics and the making of blackpowder. A crusher is a dumb mother fucker on usw who cant use his own account to say stupid shit. ... An ore is a mineral deposit containing a metal or other valuable resource in economically viable concentrations. ... In metallurgy, stainless steel (inox) is defined as a ferrous alloy with a minimum of 10. ... A pulley is a wheel with a groove along its edge, for holding a rope or cable. ... Tumble polishing, or tumbling, is a technique for smoothing and polishing a hard substance. ...