An apparatus for separating out light materials from mineral raw materials is provided. The apparatus includes a charging device that has a charging tube provided with an eccentrically arranged inlet for tangential introduction of raw material. The apparatus also has an inner chamber for separating out coarse sand received from the charging tube, and an outer chamber that serves for sorting out fine sand pursuant to the fluidized bed process. The outer chamber communicates with an overflow chute of the charging tube via an inclined overflow surface. An impingement body is centrally disposed in the inner chamber while leaving free an outer annular gap. The charging tube opens out centrally above the impingement body. A perforated basket, for adjusting flow resistance, is disposed so as to be displaceable in the axis of the charging tube and bridges a space between the impingement body and the end of the charging tube. The overflow chute of the charging tube is provided at that end thereof remote from the impingement body. As a function of a separation particle size setting of the charging device, which is adjusted by displacement of the perforated basket, the overflow chute communicates either with the outer chamber or with a light material overflow associated therewith.