From p. 12 of the ALLIANT POWDER Reloaders' Gide, about half-way down the page:
" Alliant propellants are extruded and cut into circular flakes or cylinders by precision dies and cutting equipment. Granule size tolerances are very tight and uniform to prevent separation of different size granules and to ensure consistent ballistic performance, load after load."
So it is technically, a "granule", but it really is (and looks like) a "FLAKE".
And it is an interesting read, if you haven't done it by now. Highly recommended for reloaders who want to know what is going on, and even more so for those who just want to load and shoot.