"RIV/61989592:15310/12:33141000!RIV13-MSM-15310___" . "\u010Cuda, Jan" . . "Fe; M\u00F6ssbauer; chemistry; Mn-tourmaline; dravite series; site occupancies; chemical-composition; ferric-iron; heat-treatment; crystal-structure"@en . "Tu\u010Dek, Ji\u0159\u00ED" . "18"^^ . "We present a detailed study of thermally-driven oxidation and reduction of Fe in the structure of schorl (as the most widespread tourmaline), Fe2+-bearing olenite and fluor-schorl. The principal Fe3+-rich tourmaline investigated in this study is a natural schorl sample from a unique occurrence in peralkaline rocks near Cancrinite Hill, east of Bancroft, southern Ontario. Tourmaline samples were thermally-treated in air and hydrogen at temperatures of 700, 800 and 900 \u00B0C to oxidize or reduce the structural Fe. High-temperature changes were continuously monitored using 57Fe M\u00F6ssbauer and infrared spectroscopy. Proportions of Fe2+ and Fe3+ vary as a function of the heat treatment. An increase in Fe3+ up to 100% after heating in air at 700 \u00B0C was observed, whereas only small changes in the Fe3+/Fetot ratio after heating under hydrogen at 700 \u00B0C was revealed. Partial deprotonation/protonation represents charge compensation for the oxidation/reduction of Fe at the Y and Z sites." . . "P(ED2.1.00/03.0058), P(GAP210/10/0743), Z(MSM6198959218)" . "Nov\u00E1k, Milan" . . "Iron redox reactions in the tourmaline structure: High-temperature treatment of Fe3+-rich schorl" . . "10.1016/j.gca.2012.02.031" . "Bosi, Ferdinando" . . "Iron redox reactions in the tourmaline structure: High-temperature treatment of Fe3+-rich schorl"@en . "Wildner, Manfred" . "We present a detailed study of thermally-driven oxidation and reduction of Fe in the structure of schorl (as the most widespread tourmaline), Fe2+-bearing olenite and fluor-schorl. The principal Fe3+-rich tourmaline investigated in this study is a natural schorl sample from a unique occurrence in peralkaline rocks near Cancrinite Hill, east of Bancroft, southern Ontario. Tourmaline samples were thermally-treated in air and hydrogen at temperatures of 700, 800 and 900 \u00B0C to oxidize or reduce the structural Fe. High-temperature changes were continuously monitored using 57Fe M\u00F6ssbauer and infrared spectroscopy. Proportions of Fe2+ and Fe3+ vary as a function of the heat treatment. An increase in Fe3+ up to 100% after heating in air at 700 \u00B0C was observed, whereas only small changes in the Fe3+/Fetot ratio after heating under hydrogen at 700 \u00B0C was revealed. Partial deprotonation/protonation represents charge compensation for the oxidation/reduction of Fe at the Y and Z sites."@en . . . "0016-7037" . . . "Iron redox reactions in the tourmaline structure: High-temperature treatment of Fe3+-rich schorl"@en . . "GB - Spojen\u00E9 kr\u00E1lovstv\u00ED Velk\u00E9 Brit\u00E1nie a Severn\u00EDho Irska" . "000303677400016" . . "Skogby, Henrik" . "RIV/61989592:15310/12:33141000" . . "15310" . "Iron redox reactions in the tourmaline structure: High-temperature treatment of Fe3+-rich schorl" . . . . . "3"^^ . "86" . . . . "143041" . "JUN" . . . . "7"^^ . . "Geochimica et Cosmochimica Acta" . "Filip, Jan" . "[A8C03B0FDFB8]" . . . . . .