There seems to be a misunderstanding:
Naniwa, Shapton, Norton... they all use the same abrasive!
White Al2O3.
Al2O3 IS a ceramic material. It is THE ceramic material when we speak of hones.
There are others like SiC, but those are uncommon amongst the big brands.
So I never really understood why some of these stones are called
"ceramic hones". Of course they are ceramic. The abrasive is ceramic.
Itīs always... (except some naturals and exotics)
Al2O3 always comes in splinters, whereas Chromium Oxide, iron oxide and some garnets can appear in round shape.
Diamonds are splinters as well.
There are two things that seperate the shaptons from the naniwas
Its the binder (thatīs what is referred to when it is spoken of "mixtures")
and the purity of particle sizes.
The latter is quite obvious.
There is no way a shapton 16k can consist of 100% particles with 0.92ĩm in diameter.
You will always have like 10% above 1ĩ, 10% below 0.92ĩm and so on
The grade of purity will have impact on the quality of the surface and sharpening results
The binder is what we will actually feel.
If a stone is "hard" itīs not the Al2O3 we are talking about,
itīs the binder.
White Al2O3 will nearly always have the same hardness.
But if these hard particles are bond very very loosely
the sharpening experience as well as the results will be very different
from a stone with a harder binder.
I belive the binder will most certainly have impact on the size, depth and occurance of scratches a stone produces
even with the exact same type of abrasive in it
(wich is the case in naniwa, shapton and norton)
Kingfish I totally understand what your doctor meant,
studying chemistry myself
But, it is the nature of the sedimentary selecting process
that prohibits influence on shape, so either the particles will naturally form
round crystalls, or they will be splinter-shaped, I believe