Category Molybdate minerals Crystal system Monoclinic | Formula(repeating unit) Th(MoO4)2•H2O Space group P21/c | |
Crystal class Prismatic (2/m)(same H-M symbol) Unit cell a = 7.36, b = 10.54c = 9.49 [Å], β=91.88° (approximated) | ||
Nuragheite is a very rare second natural thorium molybdate, formula Th(MoO4)2•H2O, discovered in Su Seinargiu, Sarroch, Cagliari, Sardegna, Italy. This locality is also a place of discovery of the other thorium molybdate - ichnusaite, which is a trihydrate.
Contents
Occurrence and association
Nuragheite is a part of molybdenum-bismuth mineralization. It coexists with ichnusaite, muscovite, and xenotime-(Y).
Crystal structure
The crystal structure of nuragheite is composed of (100) layers with IXTh-centered polyhedra and Mo-centered tetrahedra. It is thus similar to that of ichnusaite.
References
Nuragheite Wikipedia(Text) CC BY-SA