Guérinite Ca<sub>6</sub>(HAsO<sub>4</sub>)<sub>3</sub>(AsO<sub>4</sub>)<sub>2</sub>∙10.5H<sub>2</sub>O – a revision of the mineral formula

Autor(en)
Irene Liebhart, Branko Rieck, Gerald Giester
Abstrakt

A single crystal of guérinite from the Plaka Mine, Lavrion, Greece, was examined by X-ray diffraction. The mineral crystallizes in the monoclinic space group P21/n with unit cell parameters a = 17.628 (2), b = 6.728 (1), c = 23.384 (3) Å, β = 90.68 (1)°, V = 2773.4 (6) Å3. The originally reported mineral formula Ca5(HAsO4)2(AsO4)2∙9H2O, Z = 5 should be revised to Ca6(HAsO4)3(AsO4)2∙10.5H2O, Z = 4. Accordingly, guérinite is no longer considered a polymorph to ferrarisite. The structure is characterized by complex layers consisting of corner- and edge sharing of CaOn (n = 7, 8) polyhedra and
arsenate groups. The connection between these units is achieved exclusively via hydrogen bonding.

Organisation(en)
Institut für Mineralogie und Kristallographie
Journal
Mineralogy and Petrology
Band
118
Seiten
547-554
Anzahl der Seiten
8
ISSN
0930-0708
DOI
https://doi.org/10.1007/s00710-024-00873-2
Publikationsdatum
10-2024
Peer-reviewed
Ja
ÖFOS 2012
105116 Mineralogie, 105113 Kristallographie
Schlagwörter
ASJC Scopus Sachgebiete
Geochemistry and Petrology, Geophysics
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/a3103ca0-51a4-477e-ba82-f6413e7ff9f3