Knife Blog

I wrote in the blog the other day that I would write about grind stone, so I will write about it today.
 
Most grind stones we can see nowadays are artificial ones.
 
Artificial grind stones are artificially made as their names suggest. On the other hand, natural grind stones are stone materials excavated from rocks and geological layers.
 
We use natural grind stones at the finishing part so that knives become sharper and keep sharp for longer time. It is said that this is because of shape of grind stones. Particles of most artificial grind stones are hexagonal while those of most natural grind stones are ellipsoidal. The reason why particles of most natural grind stones are ellipsoidal is that natural grind stones are made from fossils from plankton over 2 hundreds million years ago.
 
However, natural grind stones are used only by enthusiasts now because some production areas where we can get natural grind stones are closed and because qualities of artificial grind stones have become better.
 
Finally, I write about diamond grind stones although they are not artificial grind stones nor natural grind stones. As you may know, diamond is said to be the hardest in the world, so diamond grind stones can sharpen knives quickly and can be used for hard knives. However, we don’t use diamond grind stones with water unlike artificial grind stones or natural grind stones, so diamond grind stones can easily damage edges of knives. Therefore, diamond grind stones are secondarily used in most cases such as in the case of nicked edges.
 
*The whetstone on the picture is a Shouhonyama natural grind stone from Kyoto, which is a fine-grit grind stone.