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.
The Norton IM200-8” Three Stone Sharpening unit has a bench, a durable plastic case, a lid, and a reservoir in the base of the unit. The reservoir is where your lubrication liquid goes. Stones that are not being used can be submerged here so that they are kept saturated and clean, and ready for use. The rotating axis holds the stones in place and ready to use in sequence. No-slip rubber feet keep the unit sturdy and protect the stones from breaking. An angle guide is included to help you position your knife accurately. A 4.5 ounce can of Norton sharpening stone oil is also included for lubrication.
Overall, customers were satisfied with these sharpening stones. They like the reservoir that holds the oil, and the rubber feet that keeps the unit from sliding. One customer, however, felt that the rotating block caused the stones to rock slightly, throwing off the angle. Other customers loved the product and felt they obtained a factory-edge after using it. Amazon customers gave it 4.6 out of 5 stars and HomeCentric.org‘s team consider it to be the best knife sharpening stone on the market.