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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]

The new mineral species oxycalcioroméite, Ca2Sb5+2 O6O, has been discovered at the Buca della Vena mine, Stazzema, Apuan Alps, Tuscany, Italy. It occurs as euhedral octahedra, up to 0.1 mm in size, embedded in dolostone lenses in the baryte + pyrite + iron oxides ore. Associated minerals are calcite, cinnabar, derbylite, dolomite, hematite, 'mica', pyrite, sphalerite and 'tourmaline'. Oxycalcioroméite is reddish-brown in colour and transparent. It is isotropic, with ncalc = 1.950. Electron microprobe analysis gave (wt.%; n = 6) Sb2O5 63.73, TiO2 3.53, SnO2 0.28, Sb2O3 10.93, V2O3 0.68, Al2O3 0.28, PbO 0.68, FeO 5.52, MnO 0.13, CaO 13.68, Na2O 0.83, F 1.20, O = F - 0.51, total 100.96. No H2O, above the detection limit, was indicated by either infrared or micro-Raman spectroscopies. The empirical formula, based on 2 cations at the B site, is (Ca1.073Fe2+0.338Sb3+0.330Na0.118 Pb0.013Mn0.008)Σ=1.880(Sb5+ 1.734Ti0.194V0.040Al0.024Sn0.008)Σ=2.000(O6.682F0.278)Σ6.960. The crystal structure study gives a cubic unit cell, space group Fd3m, with a 10.3042(7) Å, V 1094.06(13) Å 3, Z = 8. The five strongest X-ray powder diffraction lines are [d (Å)I (visually estimated)(hkl)]: 3.105(m)(311); 2.977(s)(222); 2.576(m)(400); 1.824(ms)(440); and 1.556(ms)(622). The crystal structure of oxycalcioroméite has been solved by X-ray single-crystal study on the basis of 114 observed reflections, with a final R1 = 0.0114. It agrees with the general features of the members of the pyrochlore supergroup. [ABSTRACT FROM AUTHOR]