252981.fig.001a
(a)
252981.fig.001b
(b)
252981.fig.001c
(c)
Figure 1: SEM micrographs of mineral fillers (a) Mica (monoclinic, tendency towards pseudohexagonal crystals), (b) Zeolite (silica, and alumina tetrahedrons), (c) Vansil (wollastonite; triclinic, with lamellar, compact, and fibrous aggregates).