Referenza:
▪ Götz, E., Kleebe, H.J., Kolb, U. (2022): The hierarchical internal structure of labradorite. European Journal of Mineralogy, 34, 393–410.
Abstract:
The different structural features of labradorite and its incommensurate atomic structure have long been in the eye of science. In this transmission electron microscopy (TEM) study, all of the structural properties of labradorite could be investigated on a single crystal with an anorthite–albite–orthoclase composition of An53.4Ab41.5Or5.1. The various properties of labradorite could thus be visualized and connected to form a hierarchical structure. Both albite and pericline twins occur in the labradorite. The size of alternating Ca-rich and Ca-poor lamellae could be measured and linked to the composition and the color of labradorescence. Furthermore, a modulation vector of 0.0580(15)a* + 0.0453(33)b* − 0.1888(28)c* with a period of 3.23 nm was determined. The results indicate an eα labradorite structure, which was achieved by forming Ca-rich and Ca-poor lamellae. The average structure and subsequently the incommensurate crystal structure were solved with a three-dimensional electron diffraction (3DED) data set acquired with automated diffraction tomography (ADT) from a single lamella. The results are in good agreement with the structure solved by X-ray diffraction and demonstrate that 3DED–ADT is suitable for solving even incommensurate structures.
The hierarchical internal structure of "labradorite"
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
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The hierarchical internal structure of "labradorite"
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Massimo Russo
- Messaggi: 7920
- Iscritto il: mar 29 giu, 2004 12:00
- Località: via Consalvo, 120/A, I-80125 Napoli
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Re: The hierarchical internal structure of "labradorite"
Ma perché si continua a parlare di labradorite se l'IMA l'ha eliminata?
Massimo
Massimo
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Massimo Russo
INGV - Osservatorio Vesuviano
"Un minerale senza nome è solo un inutile pezzo di pietra" (Massimo Russo)
Massimo Russo
INGV - Osservatorio Vesuviano
"Un minerale senza nome è solo un inutile pezzo di pietra" (Massimo Russo)
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: The hierarchical internal structure of "labradorite"
Nello specifico perché questo membro intermedio tra albite e anortite ha una sua specifica struttura cristallina.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
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