Thank you. How can we test the stones on how fine they are? Yes, shaving with them, but, there are many stones around 1k or 4k or somewhere around there. Stones that are not the best finishers. Accept from the tongue trick, that has been used for centuries (somewhat accurate method), are there any other options? How shiny the razor gets? Or the stone? What do we do then? I don't wanna hear "we strop it and see how fine it shaves". Are there any other options? No microscope.