| Rozenite | |
| Category: | Sulfate mineral |
| Formula: | Fe2+SO4·4(H2O) |
| Imasymbol: | Rzn[1] |
| Strunz: | 7.CB.15 |
| Dana: | 29.06.06.01 |
| System: | Monoclinic |
| Class: | Prismatic (2/m) (same H-M symbol) |
| Symmetry: | P21/n |
| Color: | Colorless, white, pale green |
| Habit: | As concretions and nodules; most commonly as powdery efflorescences or coatings on melanterite |
| Mohs: | 2–3 |
| Luster: | Vitreous to dull |
| Streak: | White |
| Diaphaneity: | Semitransparent |
| Gravity: | 2.29 |
| Opticalprop: | Biaxial (−) |
| Refractive: | nα = 1.526 – 1.528 nβ = 1.536 – 1.537 nγ = 1.541 – 1.545 |
| Solubility: | Water soluble |
| References: | [2] [3] [4] |
Rozenite is a hydrous iron sulfate mineral, Fe2+SO4·4(H2O).
It occurs as a secondary mineral, formed under low humidity at less than as an alteration of copper-free melanterite, which is a post mine alteration product of pyrite or marcasite. It also occurs in lacustrine sediments and coal seams. Associated minerals include melanterite, epsomite, jarosite, gypsum, sulfur, pyrite, marcasite and limonite.[2]
It was first described in 1960 for an occurrence on Ornak Mountain, Western Tatra Mountains, Małopolskie, Poland. It was named for Polish mineralogist Zygmunt Rozen (1874–1936).[2] [3]
The thermal expansion of rozenite was studied from to using neutron diffraction. Rozenite exhibits negative linear thermal expansion, meaning that it expands in one direction upon cooling.[5]