Schaurteite, Ca3Ge(SO4)2(OH)6·3H2O

• Main Authors: Marcus J. Origlieri, Robert T. Downs
• Format: Article
• Language: English
• Published: International Union of Crystallography 2013-02-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536812050945

This report presents the first crystal structure determination of the mineral schaurteite, ideally Ca3Ge(SO4)2(OH)6·3H2O, tricalcium germanium bis(sulfate) hexahydroxide trihydrate. This single-crystal X-ray diffraction study investigated a natural sample from the type locality at Tsumeb, Namibia. Schaurteite is a member of the fleischerite group of minerals, which also includes fleischerite, despujolsite, and mallestigite. The structure of schaurteite consists of slabs of Ca(O,OH,H2O)8 polyhedra (site symmetry mm2) interleaved with a mixed layer of Ge(OH)6 octahedra (-3m.) and SO4 tetrahedra (3m.). There are two H atoms in the asymmetric unit, both located by full-matrix refinement, and both forming O—H...O hydrogen bonds.