Unknown Mine Kiita Nashiji Awasedo Fine Grit Japanese Natural Sharpening Stone 1lb. 5.7oz. (614g)
#6000 to #10000 for medium range in the fine grit for high carbon blade
It is used vintage fine grit stone.
I do not know which mine derived from, and it looks heavy condensed stone in the size.
If I am not afraid of guessing where it from. It might be from Narutaki, Nakayama, Shobu, etc., or nearby there.
It raises very good amount of black color slurry quickly.
It is not too hard not too soft, ideal hardness to me.
It does not need tomo nagura or the device to produce the slurry (worn Diamond lapping stone).
(Scale; 1 to 10, 1-3 is very soft muddy rough grit whetstone 3-6 is soft medium grit whetstone, 6-8 is hard medium grit whetstone; 8-10 is fine grit whetstone)
It makes my pure carbon Swedish steel kasumi kiridashi blade Hagane became mirror finish.
Jigae became from kind of light frosted color finish to semi-mirror finish.
It should be excellent final razor sharpening stone to me.
(Scale; 1 to 10, 1-3 give deep scratch marks to the steel, 3-5 is delete the 1-3 scratches, 5-8 makes the steel cloudy, 8-10 makes the steel semi-mirror finish or mirror finish)
Natural whetstone has wider capacity than artificial whetstone, and actually, we do not know until sharpen blade on the hone for a while. Because artificial whetstone molecules do not break down to smaller sizes, but Natural whetstone molecules are possible to break down to smaller sizes, and those molecules are mixed with sharpened steel molecules, and make Jigane as suitable Jigane color, and Hagane as suitable Hagane color. It is natural mystics.