Cutting into a Jnat

Inside Jnat 1

Every now and then I find a Jnat that has an obvious issue that precludes it from being used as a razor hone. But – if I think the stone is, otherwise, of good quality, I try to save it. They are usually less expensive, and with a little work they can be great razor hones. 

Cutting into a Jnat can turn up surprises and additional hurdles.

The photo above shows a difficult scenario, but it’s not terminal.

The surgery saved the stone and it produced two very nice Tomo Nagura.


I was raised in a home where cutting stones, gems and semi-precious, was a regular event. My grandfather was a well-known lapidary, and my Dad learned from him and I learned from both of them. So cutting stones isn’t new to me. The cut you see above was done with a hacksaw. Cutting stone by hand might seem to be overly labor-intensive; some type of power tool might seem to be more sensible. 

The simple truth is that Jnats are, as you see above, sometimes riddled with flaws. The excessive heat and vibrations from many power tools can cause what is actually a stable distraction to become unstable; which can turn a nice stone into rubble almost instantly. 

The stone in the photo was cut off of a Jnat with two few problematic areas in the working surface. To use this stone for honing razors, the issues had to be relieved.   

The two lines bisecting the stone are porous non-toxic mineral lines; if left untreated, they would take on water causing them to swell while softening the surrounding stone. These two forces would cause the stone to split. 

Additionally, those seams ran on an angle to the stone’s surface, as a result, the termination points merged and the surface area they occupied was quite large. Cutting off the part of the stone that showed the end of these lines brought the termination points to the edge of the stone, where they can be sealed and forgotten about for 40-50 years or so. 

© Keith V Johnson 2014 - 2018