Belgian Coticule sharpening stones are natural-earth stones with unique sharpening abilities.  The yellow Coticule stone is often used as a razor hone and is an extra-fine 8000 grit.  The Coticule is popular with straight-razor users, woodworkers and knife-enthusiasts who want the very best. 

Belgian sharpening stones contain a large percentage of garnet crystals. Garnet is only third in hardness behind diamond and corundum.  The unique shape of the crystals together with their hardness results in a combination of fast cutting and fine honing that is unmatched by other stones. 

The Blue Stone is 4000 grit and composed of 20-30% garnet crystals.  It is available in larger sizes up to 12" x 4" which makes it ideal for larger knives and plane blades.