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Dipartimento di Chimica - Università di Milano
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- PublicationRestrictedD’ansite-(Mn), Na21Mn2+(SO4)10Cl3 and d’ansite-(Fe), Na21Fe2+(SO4)10Cl3, two new minerals from volcanic fumaroles(2012)
; ; ; ; ; ;Demartin, F.; Dipartimento di Chimica, Universita` degli Studi di Milano, ;Campostrini, I.; Dipartimento di Chimica, Universita` degli Studi di Milano, ;Castellano, C.; Dipartimento di Chimica, Universita` degli Studi di Milano, ;Gramaccioli, C.M.; Dipartimento di Chimica, Universita` degli Studi di Milano, ;Russo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; ; ; ; The new minerals d’ansite-(Mn), Na21Mn2+(SO4)10Cl3, and d’ansite-(Fe), Na21Fe2+(SO4)10Cl3, occur as encrustations in fumaroles at Vesuvius, Naples, Italy and La Fossa crater, Vulcano, Aeolian Islands, Italy, respectively. Both minerals are cubic and crystallize in space group I4¯ 3d. D’ansite-(Mn) forms colourless translucent tristetrahedral crystals up to 0.2 mm on edge; d’ansite-(Fe) forms aggregates of colourless to white complex isometric crystals of about the same size. Chemical analyses obtained by energy-dispersive spectrometry on an electron microprobe gave the following mean compositions: d’ansite-(Mn), Na2O 39.37, MnO 3.46, MgO 0.13, SO3 49.99, Cl 6.36, O=Cl 1.44, total 97.87 wt.%, c o r r e s p o n d i n g t o a n e m p i r i c a l f o r m u l a , on t h e ba s i s o f 43 a n i o n s , of Na20.61(Mn2+ 0.79Mg0.05)S0.84S10.13O40.09Cl2.91; and d’ansite-(Fe), Na2O 39.12, FeO 4.18, MgO 0.12, SO3 49.91, Cl 6.81, O=Cl 1.54, total 98.60 wt.%, corresponding to an empirical formula of Na20.42(Fe2+ 0.94Mg0.05)S0.99S10.08O39.89Cl3.11. The six strongest reflections in the X-ray powder diffraction pattern of d’ansite-(Fe) [listed as dobs(A˚) (I) (hkl)] are as follows: 2.807(100)(044), 2.570(37)(235), 1.714(29)(129), 3.384(27)(233), 3.113(26)(134), 2.108(15)(237). The unit-cell parameters obtained from single-crystal data are 15.9291(9) and 15.882(3) A ˚ for d’ansite-(Mn) and d’ansite-(Fe), respectively. The structure of both minerals was refined, using single-crystal diffraction data, to final R parameters of 0.0309 and 0.0336 on reflections with I > 2s(I). The structure contains three independent Na sites, one of which is partially occupied by Mn2+ or Fe2+, two independent sulfate anions and one chlorine site.167 21 - PublicationOpen AccessParascandolaite, IMA 2013-092.(2013)
; ; ; ; ;Campostrini, I.; Dipartimento di Chimica - Univerità di Milano ;Demartin, F.; Dipartimento di Chimica - Univerità di Milano ;Castellano, C.; Dipartimento di Chimica - Università di Milano ;Russo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; ; ; The new mineral parascandolaite is the natural analog of the synthetic fluoride KMgF3. It was found as a volcanic sublimate at Vesuvius volcano on 1944 eruption.160 254 - PublicationRestrictedParascandolaite, KMgF3, a new perovskite-type-fluoride from Vesuvius(2014)
; ; ; ; ;Campostrini, I.; Dipartimento di Chimica - Univerità di Milano ;Demartin, F.; Dipartimento di Chimica - Univerità di Milano ;Castellano, C.; Dipartimento di Chimica - Università di Milano ;Russo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; ; ; The new mineral parascandolaite, isotypic to cubic perovskites, space group Pm3m (no. 221) is the natural analog of the synthetic fluoride KMgF3 and is related to neighborite, NaMgF3. It was found as a volcanic sublimate at Vesuvius volcano on 1944 eruption lava scoria, associated with opal, cerussite, mimetite, phoenicochroite and coulsellite. It occurs as transparent colorless to white cubic crystals up to 0.5 mm in length with vitreous luster. The density measured by flotation in a diiodomethane–toluene mixture is 3.11(1) g/cm3; that calculated from the empirical formula and single-crystal X-ray data is 3.123 g/cm3. The mineral is isotropic with n = 1.395(5) (580 nm). The six strongest reflections in the X-ray powder diffraction pattern are: [dobs in Å(I)(h k l)] 2.001(100)(2 0 0), 2.831(83) (1 1 0), 2.311(78)(1 1 1), 1.415(56)(2 2 0), 1.633(35) (2 1 1) and 1.206(22)(3 1 1). The unit-cell parameter is a = 4.0032(9) Å. The structure was refined to a final R(F) = 0.0149 for 35 independent observed reflections [I > 2σ(I)]. The mineral is named after the Italian mineralogist Antonio Parascandola (1902–1977).254 63 - PublicationOpen AccessD’ansite-(Mn), IMA 2011-064. CNMNC Newsletter No. 11, December 2011(2011)
; ; ; ; ; ;Campostrini, I.; Dipartimento di Chimica, Università di Milano ;Demartin, F.; Dipartimento di Chimica, Università di Milano ;Castellano, C.; Dipartimento di Chimica, Università di Milano ;Gramaccioli, C.M.; Dipartimento di Chimica, Università di Milano ;Russo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; ; ; ; Mn2+-analogue of d'ansite161 133 - PublicationOpen AccessParadimorphite, IMA 2020-101 in (IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 66(2022)
; ; ; ; ; ; ; ; ; ; ; The information given here is provided by the IMA Com mission on New Minerals, Nomenclature and Classification for comparative purposes and as a service to mineralogists working on new species....79 34