Lanthanite-(Nd) mineral

Lanthanite-(Nd) is the neodymium-dominant lanthanite mineral, approved as IMA 1979-074, with ideal formula Nd2(CO3)3(H2O)6·2H2O, equivalently Nd2(CO3)3·8H2O. It is distinct from elemental neodymium, the lanthanite group and other rare-earth carbonate species. Morrison et al. (2013) characterized a natural specimen from Mitsukoshi, Saga Prefecture, Japan. Electron-microprobe results averaged over 23 analysis points gave a mixed rare-earth composition with Nd0.95La0.61Pr0.17Sm0.12Gd0.08Y0.04Eu0.03 per two rare-earth cations in the reported empirical formula; water was assigned by difference. This is specimen chemistry, not a pure neodymium end-member, ore grade or recovered-metal yield. Single-crystal X-ray diffraction at 296 K resolved an orthorhombic Pccn structure containing sheets of rare-earth coordination polyhedra and carbonate groups. All rare-earth elements were modeled as Nd because of their similar X-ray scattering, so this refinement does not determine their individual site distributions. Water hydrogen positions could not be assigned reliably and were excluded from refinement; the proposed hydrogen-bond connections rely on oxygen geometry and bond-valence interpretation. The original CIF and reflection downloads remain unverified despite access to the complete article and its rendered supplementary crystallographic information. This record establishes identity and characterization without asserting microbial formation, extraction performance, industrial deployment or a jurisdiction-specific criticality designation.

Record source: data/records/lanthanite-nd.yaml