Derived from ground up polishing stones, uchiko is a fine powder that when used sparingly helps maintain the surface finish of your nihonto's blade.
This is unsuitable for use on iaito, it will damage the finish considerably. When using on nihonto, use sparingly so as not to degrade your sword.
The ground whetstones are double wrapped in silk to allow for fine and controlled application. The deluxe grade is more finely ground than the standard.