Crystal-chemistry by X-ray structure refinement and electron microprobe analysis of a series of sodic-calcic to alkali- amphiboles from the Nybo eclogite pod, Norway.

L. Ungaretti, D. C. Smith, G. Rossi

Research output: Contribution to journalArticlepeer-review

49 Scopus citations

Abstract

The crystal structures of 21 amphibole crystals from a single 16 cm-thick layered sample from the Nybo pod, Nordfjord, W Norway, have been refined. Most compositions lie between winchite and the two end-members which are the most substituted Fe-free amphiboles: NaNa2Mg3Al2Si7AlO22(OH)2 here termed nyboite and NaCaNaMg3Al2Si6Al2O22(OH)2, magnesio-alumino-taramite. The main compositional relationships can be explained by a combination of local bulk chemical control, P-T conditions, and site occupancies, thus enabling approximate site occupancy determinations from cell dimensions alone. It is claimed that chemical analyses by XRD structure refinement without chemical restraints are comparable in accuracy to electron microprobe analyses of the same crystals. -R.A.H.

Original languageEnglish
Pages (from-to)400-412
Number of pages13
JournalBulletin de Mineralogie
Volume104
Issue number4
DOIs
StatePublished - 1981
Externally publishedYes

Fingerprint

Dive into the research topics of 'Crystal-chemistry by X-ray structure refinement and electron microprobe analysis of a series of sodic-calcic to alkali- amphiboles from the Nybo eclogite pod, Norway.'. Together they form a unique fingerprint.

Cite this