Narutaki akapin kiita. This graphic form of black karasu is a manganese intrusion that occurs at the later stage of sedimentation. It does not affect the utility of the stone one way or the other. The hardness is 3- on the Mohs scale. There is one tight shallow inclusion on the back that hosts at an intersection a harder Al2o3 component. This can be managed so as to not affect the use of the stone.
The sides and ends of this stone were hand-sawn at the mine over a hundred years ago and are now sealed with spar varnish.
A true razor-grade stone with super fine grit, it will hone a host of steel types. A generous tested tomonagura slurry stone will be included.
190 x 67 x 25mm thick
$950
#218 Narutaki kiita bench stone
All of my stones are sold with a money-back guarantee minus the return shipping if within 30 days of the sale and returned in their original state. Please do not lacquer the stone if you have any intention of returning it.
I encourage sealing the sides of all sedimentary stones, especially if there a inclusions, cracks, or fissures and or if the stone is used in an active workshop where the stone is constantly wet. For casual use, sealing, especially all four sides, and preferably the back with one of either a marine type of spar varnish, a synthetic lacquer, urushi, or a cashew-derived lacquer is prudent.