Batoniite, [Al8(OH)14(H2O)18](SO4)5 ⋅ 5H2O, a new mineral with the [Al8(OH)14(H2O)18]10+ polyoxocation from the Cetine di Cotorniano Mine, Tuscany, Italy
D. Mauro, C. Biagioni, J. Sejkora, Z. Dolníček, R. Škoda
{"title":"Batoniite, [Al8(OH)14(H2O)18](SO4)5 ⋅ 5H2O, a new mineral with the [Al8(OH)14(H2O)18]10+ polyoxocation from the Cetine di Cotorniano Mine, Tuscany, Italy","authors":"D. Mauro, C. Biagioni, J. Sejkora, Z. Dolníček, R. Škoda","doi":"10.5194/ejm-35-703-2023","DOIUrl":null,"url":null,"abstract":"Abstract. The new mineral batoniite,\n[Al8(OH)14(H2O)18](SO4)5 ⋅ 5H2O,\nwas discovered in the Cetine di Cotorniano Mine, Chiusdino, Siena,\nTuscany, Italy. It occurs as hemispherical aggregates composed of brittle\ntabular crystals, up to 1 mm in size, white to colorless in color, with a\nwhite streak and a vitreous to greasy luster. Batoniite is biaxial negative,\nwith α= 1.4833(6), β= 1.4948(6), γ= 1.5019(5)\n(589 nm), and 2V(meas.)= 71(1)∘. Electron microprobe\nanalysis, affected by the dehydration of batoniite under the chamber vacuum,\ngave (in wt %) the following: Al2O3 33.48, Fe2O3 0.05, SO3\n33.00, and H2Ocalc 44.41, total 110.94. It corresponds to the chemical\nformula (Al7.98Fe0.013+)Σ7.99(SO4)5.01(OH)13.95(H2O)18 ⋅ 5H2O. Batoniite is triclinic, belonging to space group P1‾, with a= 9.1757(6), b= 12.0886(9), c= 20.9218(15) Å, α= 82.901(3),\nβ= 87.334(3), γ= 86.999(2)∘, V= 2297.8(3) Å3, and Z= 2. The crystal structure was refined to R1= 0.0916\nfor 8118 unique reflections with Fo>4σ(Fo) and\n811 refined parameters and 60 restraints. Batoniite is characterized by\nisolated [Al8(OH)14(H2O)18]10+ polyoxocations,\nH-bonded to five interstitial (SO4)2− and five H2O groups. In\ntype material, it is associated with gypsum and a poorly crystallized Al–Fe\nsulfate. The crystallization of batoniite is probably due to the action of\nH2SO4 on Al-bearing rocks of Paleozoic age cropping out in the\nGaribaldi Tunnel, the lowest mining level of the Cetine di Cotorniano Mine.\n","PeriodicalId":11971,"journal":{"name":"European Journal of Mineralogy","volume":" ","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Mineralogy","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.5194/ejm-35-703-2023","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MINERALOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Abstract. The new mineral batoniite,
[Al8(OH)14(H2O)18](SO4)5 ⋅ 5H2O,
was discovered in the Cetine di Cotorniano Mine, Chiusdino, Siena,
Tuscany, Italy. It occurs as hemispherical aggregates composed of brittle
tabular crystals, up to 1 mm in size, white to colorless in color, with a
white streak and a vitreous to greasy luster. Batoniite is biaxial negative,
with α= 1.4833(6), β= 1.4948(6), γ= 1.5019(5)
(589 nm), and 2V(meas.)= 71(1)∘. Electron microprobe
analysis, affected by the dehydration of batoniite under the chamber vacuum,
gave (in wt %) the following: Al2O3 33.48, Fe2O3 0.05, SO3
33.00, and H2Ocalc 44.41, total 110.94. It corresponds to the chemical
formula (Al7.98Fe0.013+)Σ7.99(SO4)5.01(OH)13.95(H2O)18 ⋅ 5H2O. Batoniite is triclinic, belonging to space group P1‾, with a= 9.1757(6), b= 12.0886(9), c= 20.9218(15) Å, α= 82.901(3),
β= 87.334(3), γ= 86.999(2)∘, V= 2297.8(3) Å3, and Z= 2. The crystal structure was refined to R1= 0.0916
for 8118 unique reflections with Fo>4σ(Fo) and
811 refined parameters and 60 restraints. Batoniite is characterized by
isolated [Al8(OH)14(H2O)18]10+ polyoxocations,
H-bonded to five interstitial (SO4)2− and five H2O groups. In
type material, it is associated with gypsum and a poorly crystallized Al–Fe
sulfate. The crystallization of batoniite is probably due to the action of
H2SO4 on Al-bearing rocks of Paleozoic age cropping out in the
Garibaldi Tunnel, the lowest mining level of the Cetine di Cotorniano Mine.
期刊介绍:
EJM was founded to reach a large audience on an international scale and also for achieving closer cooperation of European countries in the publication of scientific results. The founding societies have set themselves the task of publishing a journal of the highest standard open to all scientists performing mineralogical research in the widest sense of the term, all over the world. Contributions will therefore be published primarily in English.
EJM publishes original papers, review articles and letters dealing with the mineralogical sciences s.l., primarily mineralogy, petrology, geochemistry, crystallography and ore deposits, but also biomineralogy, environmental, applied and technical mineralogy. Nevertheless, papers in any related field, including cultural heritage, will be considered.