This #1000 whetstone is called "Zan" meant and designed to sharpen quick. It used high quality abrasives mixed with special hard abrasives. Compared to other #1000 stones, this stone cuts material quickly. It is made harder than Kensho Zan #400 stone so that this is great for making a base shape of knife. Also, this stone is great for fixing small chippings, thinning and making base edge, and sharpening hard carbon steels.
Production method：Vitrified stone
This series (Kensho) of whetstone is recommended for someone who cares about details of sharpening, precision of sharpening, and superior sharpness. It is also good for migrating from man-made stone to natural stone.
※ There may be difference is size a bit because of hand made product
※ This is harden by high heat so that there is little difference is hardness
※ This may not change even it's sunk in water long time though, it brakes once it gets frozen