The vibrating scalpers are heavy-duty vibrating-type machinery, with a relatively small screening surface, operating with the first or second-stage crusher. They prevent fine feed, which acts as abrasive material, from entering the crusher, thus ensuring its proper operation. They are constructed in various sizes, and, in combination with a second (or even third) deck, offer the possibility of extra selection of end material. The machinery’s basic dimensions are properly adjusted to suite both the feeder and the crusher.