Prossima pubblicazione.
Referenza:
▪ Wu, B., Gu, X., Rao, C., Wang, R., Xing, X., Wan, J., Zhong, F., Bonnetti, C. (2023): Gysinite-(La), LaPb(CO3)2(OH)⋅H2O, a new rare earth mineral of the ancylite group from the Saima alkaline complex, Liaoning Province, China. Mineralogical Magazine, 87, (in press).
Abstract:
The new mineral, gysinite-(La), with the ideal formula LaPb(CO3)2(OH)·H2O, has been discovered in lujavrite from the Saima alkaline complex, Liaoning Province, China. It commonly occurs as subhedral to anhedral, granular and platy crystals of 5 to 50 μm in size, in interstices or enclosed in microcline, aegirine and nepheline. Associated minerals include nepheline, aegirine, microcline, natrolite, eudialyte, lamprophyllite, bastnäsite-(Ce), parasite-(Ce), ancylite-(La), ancylite-(Ce), bobtraillite, britholite-(Ce), thorite, calcite and galena. The crystallization of gysinite-(La) may be related to the post-magmatic carbonation event. Gysinite-(La) crystals are generally transparent, colourless, or pale yellow, with a vitreous lustre and white streak. It is brittle with an uneven fracture, and the estimated Mohs hardness is 3½ to 4. The calculated density is 5.007 g/cm3. Optically, gysinite-(La) is biaxial (–), α= 1.832(2), β= 1.849(4), γ = 1.862(5) in white light, and 2Vmeas = 81.6°. The empirical formula of gysinite-(La) is (La0.93Pb0.61Nd0.23Pr0.14Sr0.04Gd0.02Sm0.01Eu0.01Ca0.01)Σ2(CO3)2(OH)1.34·0.66H2O, which is calculated on the basis of general formula (REExM2+2-x)(CO3)2(OH)x(2-x)H2O. The strongest eight lines of its powder XRD pattern [d, Å (I, %) (hkl)] are: 5.596 (21)(011), 4.349 (100) (110), 3.732 (68) (111), 2.984 (61) (121), 2.667 (21) (031), 2.363(48) (131), 2.090 (29) (221), and 2.028 (21) (212). Gysinite-(La) is orthorhombic, in the space group Pmcn, and unit-cell parameters refined from single-crystal X-ray diffraction data are: a = 5.0655(2) Å, b = 8.5990(3) Å, c = 7.3901(4) Å, V = 321.90(2) Å3 and Z = 2. It is a new member of the ancylite group and isostructural with gysinite-(Nd), while the occupancies of La and Pb are dominant in the metal cation site in structure.
NdR: "parasite-(Ce)" = parisite-(Ce).
ancylite group
Ancylite-(Ce) SrCe(CO3)2(OH)·H2O
Ancylite-(La) SrLa(CO3)2(OH)·H2O
Calcioancylite-(Ce) CaCe3(CO3)4(OH)3·H2O
Calcioancylite-(La) CaLa(CO3)2(OH)·H2O
Calcioancylite-(Nd) Ca1.2Nd2.8(CO3)4(OH)3·H2O
Gysinite-(La) Pb2+La(CO3)2(OH)·H2O
Gysinite-(Nd) Pb2+Nd(CO3)2(OH)·H2O
Kozoite-(La) La(CO3)[(OH),H2O]
Kozoite-(Nd) Nd(CO3)[(OH),H2O]
Schuilingite-(Nd) Pb2+Cu2+Nd(CO3)3(OH)·1.5H2O
IMA 2022-008 = gysinite-(La)
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
IMA 2022-008 = gysinite-(La)
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31675
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: IMA 2022-008 = gysinite-(La)
Pubblicazione effettuata.
Referenza:
▪ Wu, B., Gu, X., Rao, C., Wang, R., Xing, X., Wan, J., Zhong, F., Bonnetti, C. (2023): Gysinite-(La), LaPb(CO3)2(OH)⋅H2O, a new rare earth mineral of the ancylite group from the Saima alkaline complex, Liaoning Province, China. Mineralogical Magazine, 87, 143-150.
Referenza:
▪ Wu, B., Gu, X., Rao, C., Wang, R., Xing, X., Wan, J., Zhong, F., Bonnetti, C. (2023): Gysinite-(La), LaPb(CO3)2(OH)⋅H2O, a new rare earth mineral of the ancylite group from the Saima alkaline complex, Liaoning Province, China. Mineralogical Magazine, 87, 143-150.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
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