We purchased this burr grinder at an Amazon Returns Outlet, so we can't return it. It grinds coffee beans if you slowly add the beans to it. If you dump them in all at once, the grinder locks up and must be cleaned. Some comments mention it locking up when grinding hard carmelized/dark coffee beans, which is what we use. It may work for medium- or light-roast coffee beans or other things, like nuts or spices.