Both energy-filtered electron diffraction and EDS data clearly indicate extraction of amorphous silica from the parent metakaolinite by electron beam heating. Compared with the extracted silica through furnace heating, a larger population with inhomogeneous distribution and higher structural disorder of extracted silica by beam heating was noticed. There is a possibility that the spinel-type phase has lower symmetry than the suggested cubic symmetry, while the < 111 > orientation of the spinel-type phase is not perpendicular to the < 001 > plane of metakaolinite. HRTEM images of mullite crystals apparently demonstrate their random orientations with respect to the parent metakaolinite.