A solid ink delivery system with discrimination feature for identifying the presence of improper ink sticks for use in solid ink printers for delivering ink to media to form an image thereon is provided. The ink delivery system includes a proper ink stick having a first feature on the stick. The ink delivery system also includes a frame and a guide connected to the frame. The guide guides the sticks in a prescribed path and cooperates with the first feature of the proper ink sticks. The ink delivery system also includes a sensor for sensing the presence of a target surface of a stick at a first position with respect to the frame. The guide cooperates with the first feature of the proper ink sticks to position the target surface of the proper ink sticks in the first position. The guide cooperates with the improper ink sticks to position the target surface of the improper ink sticks spaced from the first position so that proper ink sticks may be distinguished from improper ink sticks.