Symmetry of natural ilvaite and crystal structure of dehydrogenated ilvaite
نویسندگان
چکیده
منابع مشابه
Structural adjustments induced by heat treatment in ilvaite
Ilvaite is a mixed-valence Fe-bearing sorosilicate, typically occurring as a late forming mineral in Ca-Fe-Si skarn deposits (Burt 1971). Its chemical composition does not differ significantly from the ideal end-member, Ca Fe2Fe (Si2O7)O(OH), except for a considerable amount of Mn, mainly substituting for Fe and, to a lesser extent, Ca (Carrozzini 1994); minor replacement of Fe and Fe by Mg and...
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15 صفحه اولStructural properties and heat-induced oxidation-dehydrogenation of manganoan ilvaite from Perda Niedda mine, Sardinia, Italy
An unusually Mn-rich ilvaite sample from the Perda Niedda mine in Sardinia, Italy, was studied in order to clarify the Mn distribution among the different structural sites, and to observe the structural response of the mineral upon thermally induced oxidation-dehydrogenation. The crystal structure and the chemical composition of one crystal [a = 13.014(5), b = 8.867(3), c = 5.838(4) Å, b = 90.0...
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ژورنال
عنوان ژورنال: Acta Crystallographica Section A Foundations of Crystallography
سال: 1993
ISSN: 0108-7673
DOI: 10.1107/s0108767378093083