Pseudobrookite crystal structure

Other inorganic crystals studied by Mark and his collaborators, sometimes leading to complete structure determinations, include strontium chloride, zinc hydroxide, tin tetraiodide, potassium chlorate, potassium permanganage, and ammonium ferrocyanide. Minerals investigated by them include CaSO (anhydrite), BaSO (barite), PbSO, Fe2TiO[j (pseudobrookite), and three forms of Al2Si05 (cyanite, andalusite, and sillimanite). 

Another example lies in the development of cordierite, a desirable and stable refractory, low-thermal-expansion crystal in the Si02—AI2O3—MgO system. Here a reaction occurs between metastable phases, spinel, a-quartz, and the nucleating titanate (pseudobrookite structure) to produce cordierite and rutile as follows ... 

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