Invention relates to material breaking or milling devices for ultra-fine milling of materials. A material breaking device comprises a frame structure (1) with an upper bracket (1A) and a lower bracket (1B); a tubular housing (4) arranged between said brackets (1A, 1B). The tubular housing (4) is attached to said frame structure (1) in rotatable manner such that the tubular housing (4) rotates relative to the frame structure (1). The material breaking device further comprises at least one conical distributor (5) arranged in the tubular housing (4) and at least one outlet cone (7) arranged in the tubular housing (4) downstream from the conical distributor (5). The device further comprises a permanent magnet unit (9) attached to the tubular housing (4) such that at least two permanent magnet units (9) are provided for each milling chamber (6, 8) for creating rotating magnetic field within the milling chambers (6, 8).