Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
European Journal of Mineralogy Signup for GSW Email News
JOURNAL HOME HELP FEEDBACK/COMMNET SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
European Journal of Mineralogy; November, December 2000; v. 12; no. 6; p. 1185-1194; DOI: 10.1127/0935-1221/2000/0012-1185
© 2000 E. Schweizerbart'sche Verlagsbuchhandlung Science Publishers
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (5)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by ANDREOZZI, G. B.
Right arrow Articles by GRAZIANI, G.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation

Articles

Structural study of magnesioaxinite and its crystal-chemical relations with axinite-group minerals

Giovanni B. ANDREOZZI, Sergio LUCCHESI* and Giorgio GRAZIANI

Dipartimento di Scienze della Terra, Università di Roma "La Sapienza", P.le A. Moro 5, I-00185 Roma, Italy

* E-mail: SERGIO.LUCCHESI{at}UNIROMAI.IT

The magnesium end-member of the axinite mineral group was studied by single-crystal X-ray diffraction and refined in the P 1 space group (R = 2.2%). Cell parameters are a = 7.1381(3) Å, b = 9.1626(4) Å, c = 8.9421(4) Å, {alpha} = 91.903(4)°, ß = 98.105(3)°, {gamma} 77.468(4)°, V = 565.21(4) Å3. Magnesioaxinite is isostructural with (Mn,Fe)-axinites, but shows structural features which may account for the compositional gap observed between magnesioaxinite and manganaxinite.

Electron and ion microprobe analyses and refined site occupancies gave the following crystal chemical formula: [6][Ca2.00(Ca1.95Mn0.03)(Mg1.92Mn0.04V0.03Cr0.01)Al2.00Al2.00][4][B2.01Si8.02O30](OH1.9O0.1), very close to the ideal Mg end-membcr. The octahedron occupied by Mg (<Mg-O> = 2.17 Å) is distorted and closely connected with both tetrahedral and octahedral structure components. Its modification (when Mg substitutes for Fe2+ and Mn) causes lattice deformations and also influences T-O-T angles and geometry of octahedral sheets.

Key-words: borosilicates, axinite, magnesioaxinite, crystal structure, crystal chemistry..




This article has been cited by other articles:


Home page
 American MineralogistHome page
J. Filip, E. Dachs, J. Tucek, M. Novak, and P. Bezdicka
Low-temperature calorimetric and magnetic data for natural end-members of the axinite group
American Mineralogist, April 1, 2008; 93(4): 548 - 557.
[Abstract] [Full Text] [PDF]

Home page
 Can MineralHome page
J. Filip, J. Filip, U. Kolitsch, M. Novak, and O. Schneeweiss
THE CRYSTAL STRUCTURE OF NEAR-END-MEMBER FERROAXINITE FROM AN IRON-CONTAMINATED PEGMATITE AT MALESOV, CZECH REPUBLIC
Can Mineral, October 1, 2006; 44(5): 1159 - 1170.
[Abstract] [Full Text] [PDF]

Home page
 American MineralogistHome page
G. B. Andreozzi, S. Lucchesi, G. Graziani, and U. Russo
Site distribution of Fe2+ and Fe3+ in the axinite mineral group: New crystal-chemical formula
American Mineralogist, November 1, 2004; 89(11-12): 1763 - 1771.
[Abstract] [Full Text] [PDF]


JOURNAL HOME HELP FEEDBACK/COMMNET SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2009 by E. Schweizerbart'sche Verlagsbuchhandlung Science Publishers