Grunwerg 4 Sided Diamond Knife Sharpening Stone DW809Dfrom £21.60Compare prices4→This Grunwerg 4 sided Rockingham Forge Diamond sharpening stone has 4 different Diamond coated stainless steel coated sides for different levels of sharpening. The 200 grit is used for super coarse sh more→arpening, ideal for repairing badly damaged or very blunt blades. The 400 grit is useful for light damage and mindly blunted knives. The 600 grit is used for fine honing of a sharpened blade and the 1000 grit is for precise and super fine honing. The 4 sided sharpener has non-slip grips on each end allowing a secure position when in use. Use a 10-30° angle when sharpening a blade using light pressure for best results.