India Bench Stones, manufactured with aluminium oxide abrasive, are most popular for producing a strong, keen, long-lasting edge on high-quality tools. The frequent choice of artisans, craftsmen and mechanics. Orange/brown in colour. Oilstones should be used with oil, not water, or they will clog, but otherwise the India stone is pretty indestructible. You should never have to flatten an oilstone. Twenty five year old India stones in daily classroom use are still perfectly flat.