title: Schaurteite, Ca(3)Ge(SO(4))(2)(OH)(6)·3H(2)O.
abstract: This report presents the first crystal structure determination of the mineral schaurteite, ideally Ca(3)Ge(SO(4))(2)(OH)(6)·3H(2)O, tricalcium germanium bis-(sulfate) hexa-hydroxide 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,H(2)O)(8) polyhedra (site symmetry mm2) inter-leaved with a mixed layer of Ge(OH)(6) octa-hedra (-3m.) and SO(4) tetra-hedra (3m.). There are two H atoms in the asymmetric unit, both located by full-matrix refinement, and both forming O-H⋯O hydrogen bonds.
authors: Department of Geosciences, University of Arizona, Tucson, AZ 85721,  USA.
authors: Marcus J
authors: MJ
authors: Origlieri
authors: Robert T
authors: RT
authors: Downs