This sharpening stone system was developed by Norton Abrasives, a
world leader in products for cutting, grinding, blending sanding,
polishing, and finishing. A fine India stone and medium and coarse
Crystolon stones are included. India stones are smooth cutting
stones which come from India, and are mainly made up of aluminum
oxide. They are excellent for deburring, creating keen edges and
providing quality finishes. The India stone used with this system
is 320-grit aluminum oxide. The Crystolon stones are 100-grit and
150-grit silicon carbide stones. All Crystolon stones are created
with silicon carbide electric furnace abrasive. This process
includes ball-milling the abrasive to the right particle size. It
is then batch blended with selected bonding agents, resulting in
exact characteristics that one wants in a finishing stone. The
abrasive cuts rapidly and is harder than all natural abrasives
except diamond. Crystolon is generally used when sharpening speed
is preferred over a fine cutting edge.