• journal_title：Mineralogical Magazine
• Contributor：F. Radica ; F. Capitelli ; F. Bellatreccia ; G. Della Ventura ; A. Cavallo ; M. Piccinini ; F. C. Hawthorne
• Publisher：Mineralogical Society of Great Britain and Ireland
• Date：2013-06-01
• Format：text/html
• Language：en
• Identifier：10.1180/minmag.2013.077.4.08
• journal_abbrev：Mineralogical Magazine
• issn：0026-461X
• volume：77
• issue：4
• firstpage：485
• section：Articles

The crystal chemistry of sekaninaite from Dolní Bory, Czech Republic, was characterized by a multi-method approach. Particular emphasis was put on the characterization of the channel constituents (i.e. H₂O and CO₂). Electron microprobe analysis shows the sample to be close to the Fe endmember [m>Xm>_Fe = Fe/(Fe+Mg) = 94%) with significant Mn (1.48 wt.%) present; laser ablation mass-spectrometry showed the presence of 0.42 wt.% Li₂O. H₂O and CO₂ contents (1.48 and 0.17 wt.%, respectively) were determined via secondary-ion mass-spectrometry. Sample homogeneity was checked by Fourier-transform infrared (FTIR) imaging using a microscope equipped with a focal plane array detector. Single-crystal FTIR spectroscopy confirmed the presence of two types of H₂O groups in different orientations (with prevalence of the type II orientation), and that CO₂ is oriented preferentially normal to the crystallographic m>cm> axis. Using the Beer-Lambert relation, integrated molar coefficients, ε_i, were calculated for both types of H₂O (ε_i H₂O^[I] = 6000±2000; ε_i H₂O^[II] = 13000±1000) and for CO₂ (ε_i CO₂ = 2000±1000).