Szomolnokite
| Szomolnokite | |
|---|---|
 Halotrichite (Hal); szomolnokite (Szo) and voltaite (Vol) | |
| General | |
| Category | Sulfate mineral |
| Formula (repeating unit) | Fe2+SO4 · H2O |
| IMA symbol | Szo[1] |
| Strunz classification | 7.CB.05 |
| Dana classification | 29.6.2.2 |
| Crystal system | Monoclinic |
| Crystal class | Prismatic (2/m) |
| Space group | C2/c (no. 15) |
| Identification | |
| Color | Sulfur-yellow, yellow-brown, red-brown, blue, colorless |
| Crystal habit | Bipyramidal, distorted, tabular, parallel growths, globular, stalactites |
| Fracture | Conchoidal to sub-conchoidal, uneven |
| Tenacity | Brittle |
| Mohs scale hardness | 2.5 |
| Luster | Vitreous |
| Diaphaneity | Translucent |
| Specific gravity | 3.03–3.07 (measured), 3.10 (calculated) |
| Optical properties | Biaxial (+), colorless (transmitted light) |
| 2V angle | 80° (measured), 86° (calculated) |
| References | [2][3][4][5] |
Szomolnokite (Fe2+SO4·H2O) is a monoclinic iron sulfate mineral forming a complete solid solution with magnesium end-member kieserite (MgSO4·H2O).[2] In 1877 szomolnokite's name was derived by Joseph Krenner from its type locality of oxidized sulfide ore containing iron in Szomolnok, Slovakia (Hungary at the time).[2][3][4]
As of mid-January 2020 the only continent on which szomolnokite has not been found and reported is Antarctica.[2]
At room temperature szomolnokite is stable up to a pressure of 6.2 GPa, and then transforms into triclinic crystal structure.[6]
References
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b c d Mindat.org - Szomolnokite
- ^ a b Webmineral - Szomolnokite
- ^ a b Handbook of Mineralogy - Szomolnokite
- ^ Wildner, M.; Giester, G. (1991). "The crystal structures of kieserite-type compounds. I. Crystal structures of Me(II)SO4*H2O (Me = Mn,Fe,Co,Ni,Zn)". Neues Jahrbuch für Mineralogie - Monatshefte. 1991: 296–306.
- ^ Meusburger, J. M.; Ende, M.; Talla, D.; Wildner, M.; Miletich, R. (2019-09-01). "Transformation mechanism of the pressure-induced C2/c-to-P1¯ transition in ferrous sulfate monohydrate single crystals". Journal of Solid State Chemistry. 277: 240–252. doi:10.1016/j.jssc.2019.06.004. ISSN 0022-4596. S2CID 197070809.
Bibliography
- Palache, P.; Berman H.; Frondel, C. (1960). "Dana's System of Mineralogy, Volume II: Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. (Seventh Edition)" John Wiley and Sons, Inc., New York, pp. 479–480.