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The soft is a stone with lower density and more pores than anything we're discussing above. It's a faster cutter and less fine.

The hard that dan's sells is between the three truly hard stones...

(I can hone a razor on a pike washita, by the way, so the concern here has nothing to do with honing razors, they should all easily be fine enough with a properly conditioned surface).

Just out of curiosity, I went out to check the density of silica (specific gravity).

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2.65. (and a follow up look for novaculite shows figures of 2.66 and 2.7). I'm not surprised then that...

What I'm saying is that if you have a stone that's 2.65 and one that's 2.55, there will be a difference in fineness. Maybe not after both stones have been used for a few years, but for a while there...

Have you been able to check density? I vaguely recall measuring dan's black stone at about 2.65 SG. The trans was about the same.

The true hards may vary a little bit more from stone to stone.
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