The first example of a sandwich belt high angle conveyor delivering raw products for cement manufacture was in an underground gypsum mine; the vertical system continuously elevated gypsum. The underground crusher reduced the size of the material to under 150 mm, and dropped it onto a reciprocating plate feeder to load the sandwich belt conveyor. At the surface, the conveyor discharged onto a plant conveyor that delivered the rock either to an outside storage pile, or directly to the plant. This completely vertical system replaced a horizontal feed conveyor and bucket elevator, considerably simplifying material transport and eliminating a high-maintenance transfer point.