When it is going to be used, the stone is doused with water, and more water is poured onto it repeatedly as it is being used. Some people believe that a knife stays sharp longer if oil is used instead of water.
With time, synthetic sharpening blocks made from carborundum appeared and became the preferred type of sharpener. At first they were imported from the West, and took the form of small, light rod that could easily be taken anywhere.
Another new arrival was the motorised electrical knife sharpener which uses a spinning carborundum disc. When in use, it throws off sparks like a fireworks display. Of course, it puts a very good edge on a knife, but the sharpness does not last for long.
Another new kind of knife sharpener comes from Japan. It is usually brown and the material it is made from was very similar to natural stone — not too hard and fine in texture. When it is used to sharpen a blade, it wears away, forming a very fine, flour-like powder.
The knives in Japan are among the sharpest in the world. Japanese chefs cherish them as an important part of their lives, and are experts at giving them the keenest possible edge.
There is still one more type of knife sharpener that can either be held in the hand or attached to a table. Two lengths of the hard, sharpening material are placed at a V-shaped angle, and the knife is drawn through them to sharpen it. It is fast and easy to use.