"Martin H. Eastburn" wrote in
:




Actually, when discussing hardness, in many cases the arrangement of the
atoms in the mineral's molecules is just as important, or maybe more so,
than the chemical composition of the mineral. A good example is the
difference in hardness between diamond, the hardest mineral, and graphite,
the softest. Both are pure carbon, just difference atomica arangements.

The Mohs hardness of mica is between 2.5 and 3, pretty soft, whereas
aluminum oxide sandpaper has a Mohs hardness of around 9, so sanding seems
to me to be entirely appropriate. However, how are you going to keep the
mica from flaking to bits? I assume you either have pieces of whole
crystals which cleave into extremely thin flakes (like in your old
toaster), or you have some kind of mica composite, with shiny mica flakes
in a binder of some kind, say, epoxy or polyester resin.

Seems like sanding is the way to go, as edged tools would catch on the mica
flake edges no matter what the composition.