A modified fluidized bed separates materials differing in weight by as little as one percent. A fluidized bed is formed by directing air through vanes on an underside of a screen. Products, such as peanuts, delivered to a central portion of the screen are initially separated so that lighter weight products float on the fluidized bed and are drawn by gravity toward a lower end where a second separation takes place. The lightest products at this second end are listed over an exit weir by a controllable air jet. Desired products are not ejected and are collected.
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