A magnetic drum separator for separating components having different magnetic properties out of an aggregate material employs a drum rotatably driven on a longitudinal axis. The drum has a cylindrical shell sidewall to have an open interior wherein a magnetic array is disposed. The magnetic array is formed by a plurality of longitudinally extending and circumferentially spaced ferromagnetic bars. A first magnet is disposed between each pair of circumjacent bars, and circumjacent first magnets have similar magnetic poles facing the bar located therebetween. Second magnets extends longitudinally and a second magnet is located radially inwardly of each of a majority of the bars. Circumjacent second magnets have oppositely oriented polarities, all in the radial direction, and each second magnet has a similar pole facing the respective bar as those of the first magnets. The array is supported by an arcuate support plate and a pair of brackets secured to a rigid shaft about which the drum rotates. The array has an arcuate active surface in closely-spaced relation concentric to the drum sidewall, and this arcuate surface preferably extends between 45° and 120° of arc.

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