Abstract: A mixture of electronic component chips 2 and media 3 is placed in a planar state on a transport surface 4 of a conveyor 5. Only the media 3 are collected onto a first circulating circumferential surface 18 by a magnetic force provided by a first collection member 12 and are thereafter collected by a media collecting box 22. Then, only electronic component chips 2 having a plating film of a proper thickness formed thereon are attracted onto a second circumferential surface 28 by a magnetic force provided by a second collection member 23 and are thereafter collected by a good product collecting box 31. Electronic component chips 2a having a plating film of an insufficient thickness formed thereon are collected by a defective product collecting box 32.