This #1000 whetstone is called "Itadaki" means peak, and designed to make a base of the sharpest edge. It is made of high quality abrasives mixed with special bond so that this stone sharpen knife quickly and meantime it keeps the stone surface flatness longer. This stone can be used between Zan #1000 and Itadaki #3000. You can sharpen your blade more precisely than Zan #1000, and it cuts material quicker than Itadaki #3000. It's useful to regain knife's sharpness quickly for a rounded edge with not chippings.
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