Rozenite

Rozenite is a hydrous iron sulfate mineral, Fe²⁺SO₄•4(H₂O).

Rozenite
Rozenite from Morocco
General
Category	Sulfate mineral
Formula (repeating unit)	Fe2+SO4•4(H2O)
Strunz classification	7.CB.15
Dana classification	29.06.06.01
Crystal system	Monoclinic
Crystal class	Prismatic (2/m) (same H-M symbol)
Space group	P21/n
Identification
Color	Colorless, white, pale green
Crystal habit	As concretions and nodules; most commonly as powdery efflorescences or coatings on melanterite
Mohs scale hardness	2 - 3
Luster	Vitreous to dull
Streak	White
Diaphaneity	Semitransparent
Specific gravity	2.29
Optical properties	Biaxial (-)
Refractive index	nα = 1.526 - 1.528 nβ = 1.536 - 1.537 nγ = 1.541 - 1.545
Solubility	Water soluble
References	[1][2][3]

It occurs as a secondary mineral, formed under low humidity at less than 21 °C (70 °F) 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.^[1]

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). 

This article uses material from the Wikipedia article  Metasyntactic variable, which is released under the  Creative Commons Attribution-ShareAlike 3.0 Unported License.