Aspedamite
Appearance
Aspedamite | |
---|---|
General | |
Category | Mineral |
Formula (repeating unit) | []12(Fe3+2Fe2+)Nb4(ThNb9Fe3+2Ti4+O42)(H2O)9(OH)3 |
IMA symbol | Apd |
Identification | |
Color | Brownish orange to deep red |
Cleavage | None Observed |
Luster | Adamantine |
Streak | Very pale orange |
Specific gravity | 4.070 |
Aspedamite is a very rare mineral, one of two natural heteropolyniobates.[1] Its chemical formula (one of the possible formulas) is complex and shows the presence of essential vacancies: []12(Fe3+2Fe2+)Nb4(ThNb9Fe3+2Ti4+O42)(H2O)9(OH)3. Its structure (isometric, space group Im3) is the same as of the second known heteropolyniobate - menezesite.[2][3] Aspedamite is somewhat similar to another mineral from Norway, peterandresenite, which is a hexaniobate.[4]
References
[edit]- ^ "Aspedamite: Aspedamite mineral information and data". Mindat.org. Retrieved 2016-03-04.
- ^ Cooper, M.A., Abdu, Y.A., Ball, N.A., Černý, P., Hawthorne, F.C., and Kristiansen, R., 2012. Aspedamite, Ideally []12(Fe3+,Fe2+)3Nb4[Th(Nb,Fe3+)12O42]12{(H2O),(OH)}12, a New Heteropolyniobate Mineral Species from the Herrebøkasa Quarry, Aspedammen, Østfold, Southern Norway: Description and Crystal Structure. The Canadian Mineralogist 50, 793-804; DOI: 10.3749/canmin.50.4.793
- ^ "Menezesite: Menezesite mineral information and data". Mindat.org. Retrieved 2016-03-04.
- ^ "Peterandresenite: Peterandresenite mineral information and data". Mindat.org. Retrieved 2016-03-04.