Corundum Corundum grindstones are grindstones used universally; they have various grain sizes and shapes. They are suitable for knives, blades, milling cutters, gravers and engraving tools. Subgroups corundum blocks nameshapetypegrain sizedimensionsitem No.CorundumRectangularBench grindstonefine - medium150 x 50 x 25 mm515602CorundumRectangularBench grindstonefine - medium200 x 50 x 25 mm515612 corundum shaped stones nameshapegrain sizetypedimensionsitem No.CorundumThreesquareMediumGrindstone100 x 8 x 8mm515608CorundumSquareMediumGrindstone100 x 10 x 10mm515609