I've been flattening the backs of some chisels using
the following stones:
Norton Waterstone 220 grit
Norton Waterstone 1000 grit
Norton Waterstone 4000 grit
Shapton Professional Waterstone 8000 grit

After the Norton 4000, the chisel back is perfectly flat
and rather polished. Though I can still see scratches
by eye and with magnification, the surface is shiny and
mirror-like.

After the Shapton 8000, the surface is less shiny,
less mirror-like. The scratches seem to be finer than they
were after the 4000 Norton, but the surface is more
of a satin finish and not mirror shiny.

Just wondering what's going on here.

Thanks, Ken