FWIW, steel hardness has nothing to do with choosing stone hardness. They're not related outside of old wives tales.
Edge type is the determining factor. If you want a convex bevel, use a softer stone.
A harder stone will provide a more accurate V shape, with a thinner edge width.
It's geometry, and physics, no purple kool aid.
File that noise with the honing on distilled water story.
Anyway,
The OPs stone does not say Akapin to me.
I don't see anything that indicates Tenjyou Suita.
It could be either but given my experiences I would not lean that way.
I am not convinced the Maruka stamp is legit. Different topic for another day though.
Typically, Akapin would not bear a Maruka stamp, fwiw...
It looks to be dry and somewhat porous.
If it is very muddy when lapping and autoslurrying, then yes it's soft.
It could just very well be from Tomae, but a softer seam. There's a few in there and some are muddy/softer.
There are also stones that do not have an official name/seam/strata...I forget the Japanese name but the translation is 'plum fields'. Could be one of those.
If the stone is just releasing slurry and getting muddy without working for it, one hope to get a shaving edge is to do a few strokes and rinse. Don't make any slurry, use the stone water only and keep pressure very light. maybe try lapping the stone on 1k w/d paper. Might help. Depends on how the stone reacts to it though. Won't hurt so worth a try.
By description and look, I would not expect this stone to be very fine. I am not surprised that you are working hard to get a shaving edge. I've owned more than a few stones with similar coloring, patterning, and characteristics.
Edge type is the determining factor. If you want a convex bevel, use a softer stone.
A harder stone will provide a more accurate V shape, with a thinner edge width.
It's geometry, and physics, no purple kool aid.
File that noise with the honing on distilled water story.
Anyway,
The OPs stone does not say Akapin to me.
I don't see anything that indicates Tenjyou Suita.
It could be either but given my experiences I would not lean that way.
I am not convinced the Maruka stamp is legit. Different topic for another day though.
Typically, Akapin would not bear a Maruka stamp, fwiw...
It looks to be dry and somewhat porous.
If it is very muddy when lapping and autoslurrying, then yes it's soft.
It could just very well be from Tomae, but a softer seam. There's a few in there and some are muddy/softer.
There are also stones that do not have an official name/seam/strata...I forget the Japanese name but the translation is 'plum fields'. Could be one of those.
If the stone is just releasing slurry and getting muddy without working for it, one hope to get a shaving edge is to do a few strokes and rinse. Don't make any slurry, use the stone water only and keep pressure very light. maybe try lapping the stone on 1k w/d paper. Might help. Depends on how the stone reacts to it though. Won't hurt so worth a try.
By description and look, I would not expect this stone to be very fine. I am not surprised that you are working hard to get a shaving edge. I've owned more than a few stones with similar coloring, patterning, and characteristics.