Nuragheite
| Nuragheite | |
|---|---|
| General | |
| Category | Molybdate minerals |
| Formula (repeating unit) | Th(MoO4)2•H2O |
| Crystal system | Monoclinic - prismatic (point group 2/m) |
| Unit cell | a=7.36, b=10.54, c=9.49 [Å], β=91.88o (approximated) |
| Identification | |
| Color | Colorless |
| Crystal habit | Thin tablets |
| Crystal symmetry | Monoclinic, space group P21/c |
| Cleavage | {100}, perfect |
| Tenacity | Brittle |
| Luster | Pearly adamantine |
| Streak | White |
| Density | 5.15 (calc., approximated) |
| References | [1][2] |
Nuragheite is a very rare[2] second natural thorium molybdate, formula Th(MoO4)2•H2O, discovered in Su Seinargiu, Sarroch, Cagliari, Sardegna, Italy.[1] This locality is also a place of discovery of the other thorium molybdate - ichnusaite, which is a trihydrate.[3]
Occurrence and association
Nuragheite is a part of molybdenum-bismuth mineralization. It coexists with ichnusaite, muscovite, and xenotime-(Y).[1]
Notes on chemistry
Nuragheite is chemically pure.[1]
Crystal structure
The crystal structure of nuragheite is composed of (100) layers with IXTh-centered polyhedra and Mo-centered tetrahedra.[1] It is thus similar to that of ichnusaite.
References
- 1 2 3 4 5 Orlandi, P., Biagioni, C., Bindi, L., and Merlino, S., 2015. Nuragheite, Th(MoO4)2·H2O, the second natural thorium molybdate and its relationships to ichnusaite and synthetic Th(MoO4)2. American Mineralogist 100(1), 267-273
- 1 2 "Nuragheite - Mindat.org". Mindat.org. Retrieved 2016-03-12.
- ↑ Orlandi, Paolo; Biagioni, Cristian; Bindi, Luca; Nestola, Fabrizio (2014-10-01). "Ichnusaite, Th(MoO4)2·3H2O, the first natural thorium molybdate: Occurrence, description, and crystal structure". American Mineralogist 99 (10): 2089–2094. doi:10.2138/am-2014-4844. ISSN 0003-004X.
This article is issued from Wikipedia - version of the Wednesday, April 27, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.