Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic Time
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral Quiz
Photo SearchPhoto GalleriesSearch by ColorNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Mineralogical ClassificationRobinsonite: structure

21st Jan 2004 09:28 UTCMarco E. Ciriotti

Title: Structure refinement of natural robinsonite, Pb4Sb6S13: cation distribution and modular description

Author(s): Emil Makovicky ; Tonci Balic-unic ; Ljiljana Karanovic ; Dejan Poleti ; Jaroslav Pršek

Source: Neues Jahrbuch für Mineralogie - Monatshefte Volume: 2004 Number: 2 Page: 49 -- 67



Abstract: Crystal structure of robinsonite from the locality Malé elezné, Nízke Tatry Mountains, Slovakia, has been refined using single-crystal data (MoKα X-ray diffraction, CCD area detector) to the conventional R-factor: R1 = 0.045. Robinsonite crystallizes in the space group I2/m, with a = 23.642(4), b = 3.9761(6), c = 24.420(4)Å, β = 93.808(3) and Z = 4. X-ray diffraction and chemical analysis resulted in comparable formulae, Pb4.03Sb5.97S13 and Pb3.93Sb5.77 S13, respectively, which are close to the ideal formula Pb4Sb6S13.

Robinsonite is a member of a large family of rod-based sulphosalts, composed of rods of SnS (or TlI) archetype. In robinsonite, two types of rods, respectively 2 and 3 Sb coordination pyramids broad, combine. Their arrangement results in two types of rod-layers, denoted according to their inter-rod connections as Type 1 and Type 4, respectively. In the former case, a tightly bonded double-layer continues from one rod into the other. In the latter, the rods are interconnected by the smallest possible fragment of SnS-like configuration that is rotated 90° in respect to the SnSlike (TlI-like) arrangement in the rod interiors.

The mixed cation sites are the main characteristic of the robinsonite structure. The present study is the second one performed on natural robinsonite and the first in which all mixed positions are successfully refined. The mixed sites are concentrated in slabs parallel to <010>. The composition of these slabs can be explained by the necessity to match dimensions of the structure motifs across a noncommensurate interspace. Comparison with monoclinic boulangerite shows many similarities in distribution of mixed cation sites.
 
Mineral and/or Locality  
Mindat Discussions Facebook Logo Instagram Logo Discord Logo
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 25, 2024 08:06:03
Go to top of page