Texture analyses of pseudomorphs of silica minerals

Abstract

Metastable phases of silica minerals, which are opal, cristobalite, moganite, melanophlogite, chibaite, etc, precipitate under low-temperature hydrothermal solutions. The metastable silica minerals change to the stable phase quartz. After the phase transition, the crystal shapes remain intact, and pseudomorphs after the metastable minerals are observed. We carried out crystallographical analyses for the textures of the pseudomorphs after the metastable minerals by using scanning and transmission electron microscopes and EBSD method.