Abstract
Crystal structures of intergrown lindstromite and krupkaite were determined in two distinct samples by a simultaneous crystal-structure refinement using a modified JANA program package. The exsolution intergrowths have a bulk composition, determined by means of electron microprobe, equal to bd(60.1) and bd(64.1), respectively. The subscript indicates a percentage of the aikinite component in this bismuthinite derivative. The crystal Structure of lindstromite contains two aikinite-like ribbons Cu2Pb2Bi3S6 and eight krupkaite-like ribbons (ideally CuPbBi3S6) in a unit cell. The latter are oversubstituted; the ideally empty tetrahedral sites associated with them refined to the occupancy values of 0.04-0.09 Cu and 0.14-0.18 Cu, respectively, for the two above bulk compositions. The refined phase-compositions are Cu6.26Pb6.26Bi13.74S30 (bd(62.6)) associated with CuPbBi3S6 (bd(50)) for the sample 'bd(60)' and Cu6.64Pb6.64Bi13.36S30 (bd(66.4)) associated with oversubstituted krupkaite, the composition of which could not been refined, for the sample 'bd(64)'. From stoichiometry calculations, the latter is similar to bd(60). Both latter values may be somewhat overestimated as a result of cross-correlations between the two closely related structures during the refinement.
| Original language | English |
|---|---|
| Journal | Canadian Mineralogist |
| Volume | 46 |
| Issue number | 2 |
| Pages (from-to) | 525-539 |
| ISSN | 0008-4476 |
| DOIs | |
| Publication status | Published - 2008 |
Keywords
- Faculty of Science
- lindstromite
- oversubstitution; bismuthinite-aikinite series
- Simultaneous structure refinement
- crystal structure
- krupkaite