System, method and apparatus for processing bone product

A comminution apparatus for bone product configured to receive bone product and comminute it to a size of less than 0.1 mm, comprising:

• a pair of rigid rollers rotatably located with respect of each other to define a gap of between 0.02 mm to 0.4 mm,
• a drive counter rotationally driving the rollers to a relative rotational speed ratio of not greater than 2:1,
• at least one of the rollers having a surface with one or both of surface texturing and surface shaping applied to it, the surface shaping and surface texturing having a depth of at most 0.025 mm.