1. Deveroite-(Ce): a new REE-oxalate from Mount Cervandone, Devero Valley, Western-Central Alps, Italy.
- Author
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GUASTONI, A., NESTOLA, F., GENTILE, P., ZORZI, F., ALVARO, M., LANZA, A., PERUZZO, L., SCHIAZZA, M., and CASATI, N. M.
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CLASSIFICATION of minerals , *MINERAL analysis , *MOUNTAINS - Abstract
Deveroite-(Ce), ideally Ce2(C2O4)3.10H2O, is a new mineral (IMA 2013-003) found in the alpine fissures of Mount Cervandone, overlooking the Devero Valley, Piedmont, Italy. It occurs as sprays of colourless elongated tabular, acicular prisms only on cervandonite-(Ce). It has a white streak, a vitreous lustre, is not fluorescent and has a hardness of 2-2.5 (Mohs' scale). The tenacity is brittle and the crystals have a perfect cleavage along {010}. The calculated density is 2.352 g/cm3. Deveroite-(Ce) is biaxial (-) with 2V of ∼77°, is not pleochroic and the extinction angle (β c) is ∼27°. No twinning was observed. Electron microprobe analyses gave the following chemical formula: (Ce1.01Nd0.33La0.32Pr0.11Y0.11Sm0.01Pb0.04U0.03Th0.01Ca0.04)2.01(C2O4)2.99.9.99H2O. Although synchrotron radiation was not used to solve the structure of deveroite-(Ce) the extremely small size of the sample (13 μm×3 μm×1 μm) did not allow us to obtain reliable structural data. However, it was possible to determine the space group (monoclinic, P21/c) and the unit-cell parameters, which are: a = 11.240(8) Å, b = 9.635(11) Å , c = 10.339(12) Å, b = 114.41(10)°, V = 1019.6 Å3. The strongest lines in the powder diffraction pattern [d in Å (I)(hkl)] are: 10.266(100)(100); 4.816(35.26)(211); 3.415(27.83)(300); 5.125(24.70)(200); and 4.988(22.98)(111). Deveroite-(Ce) is named in recognition of Devero valley and Devero Natural Park. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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