Ferroberaunite, Fe2+Fe3+5 (PO4)4(OH)5⋅6H2O, a mixed-valence iron member of the beraunite series, from the Gravel Hill mine, Perranzabuloe, Cornwall, England
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F22%3A00000186" target="_blank" >RIV/00025798:_____/22:00000186 - isvavai.cz</a>
Alternative codes found
RIV/00023272:_____/22:10135664
Result on the web
<a href="https://pubs.geoscienceworld.org/minmag/article/86/3/363/616054/Ferroberaunite-Fe2-Fe3-5-PO4-4-OH-5-6H2O-a-mixed" target="_blank" >https://pubs.geoscienceworld.org/minmag/article/86/3/363/616054/Ferroberaunite-Fe2-Fe3-5-PO4-4-OH-5-6H2O-a-mixed</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1180/mgm.2022.15" target="_blank" >10.1180/mgm.2022.15</a>
Alternative languages
Result language
angličtina
Original language name
Ferroberaunite, Fe2+Fe3+5 (PO4)4(OH)5⋅6H2O, a mixed-valence iron member of the beraunite series, from the Gravel Hill mine, Perranzabuloe, Cornwall, England
Original language description
The new mineral ferroberaunite, Fe2+Fe3+5 (PO4)4(OH)5⋅6H2O (IMA2021-36; symbol: Fbru), occurs in cavities of ‘limonite’ iron ore fromthe Gravel Hill mine, Perranzabuloe, Cornwall, England. Its flattened prismatic crystals up to 400 micrometer long are dark green to olive green,transparent to translucent, with a vitreous lustre, pearly on cleavages. The Mohs hardness is ∼3–4. The density measured by the flotationmethod is 2.94(2) g⋅cm–3, the calculated density is 2.907 g⋅cm–3. Ferroberaunite is biaxial (–), with alfa = 1.736(2), beta = 1.765(3), gama = 1.786(5)at 589 nm, 2Vmeas. = 68(3)°, 2Vcalc. = 79°; dispersion of optical axes is strong, r > v; orientation is Y = b; X ≈ a, Z ≈ c. Pleochroism is strong:X = bluish-green >> Z = green > Y = yellow. Electron-microprobe analyses gave the empirical formula (Fe2+0.75Ca0.01Mn0.02Fe3+0.22)sigma1.00(Fe3+4.88Al0.04)sigma4.92(PO4)4O0.11(OH)4.76⋅6H2O. Ferroberaunite is monoclinic, C2/c, with a = 20.8708(3), b = 5.1590(8),c = 19.2263(3) angstroem, beta = 93.3186(17)°, V = 2066.7(3) angstroem3 and Z = 4. The eight strongest lines in the powder X-ray diffraction pattern are[dmeas, angstroem (Irel., percent) (hkl)]: 10.410 (100) (200), 9.606 (14) (002), 7.271 (11) (202), 5.203 (4) (400), 3.467 (12) (600), 3.325 (6) (602),3.201 (6) (006), 2.600 (4) (800). The mineral is isostructural with beraunite, redefined recently as Fe3+6 (PO4)4O(OH)4⋅6H2O.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10504 - Mineralogy
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Mineralogical Magazine
ISSN
0026-461X
e-ISSN
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Volume of the periodical
86
Issue of the periodical within the volume
3
Country of publishing house
GB - UNITED KINGDOM
Number of pages
10
Pages from-to
363-372
UT code for WoS article
000799395000001
EID of the result in the Scopus database
2-s2.0-85125182803