I got my hands on some of the Uchigomori-Fingerstones that Maksim sold. I processed them into small chips.
Heres a tip: While you are in the process of making finger stones, save all the tiny chips and chunks that are too small to become fingerstones.
Save the dust, too. Put it in a mortar and grind it for a couple of minutes. This way Uchigo, which is nothing else but fine ground Uchigomori, is made.
You can use your homemade Uchigo to maintain your kitchen knives. It will remedy patina and little discolorations without ruining the kasumi finish.
Uchigo is used as cleaning agent for swords since forever. You can also use it as final step after the finger stones. Put some of the powder on a wool pad or something soft
and do some long strokes on the wet blade. If you haven't done it before I am sure you will like it!
The first of my picture shows two vials with some homemade Uchigo. One is made from Maksims Uchigomori, the other from some uknown Hazyua (probably Uchigomori as well, who knows)