Siderotil is an
iron(II) sulfate
Iron(II) sulfate or ferrous sulfate (British English: sulphate instead of sulfate) denotes a range of salts with the formula Fe SO4·''x''H2O. These compounds exist most commonly as the heptahydrate (''x'' = 7), but several values for ...
hydrate mineral with formula: FeSO
4·5H
2O which forms by the dehydration of
melanterite
Melanterite is a mineral form of hydrous iron(II) sulfate: FeSO4·7H2O. It is the iron analogue of the copper sulfate chalcanthite. It alters to siderotil by Dehydration, loss of water. It is a secondary sulfate mineral which forms from the oxida ...
.
[Mindat.org]
/ref> Copper commonly occurs substituting for iron in the structure. It typically occurs as fibrous or powdery encrustations, but may also occur as acicular triclinic
class=skin-invert-image, 180px, Triclinic (a ≠ b ≠ c ≠ a and α, β, γ, 90° pairwise different)
In crystallography, the triclinic (or anorthic) crystal system is one of the seven crystal systems. A crystal system is described by three b ...
crystals.[
It was first described in 1891 for an occurrence in the Idrija Mine, ]Idrija
Idrija (, in older sources ''Zgornja Idrija''; , ) is a town in western Slovenia. It is the seat of the Municipality of Idrija. Located in the traditional region of the Slovene Littoral and in the Gorizia Statistical Region, it is notable for it ...
, Slovenia
Slovenia, officially the Republic of Slovenia, is a country in Central Europe. It borders Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the south and southeast, and a short (46.6 km) coastline within the Adriati ...
. Its name derives from the Greek ''sideros'' (iron) and ''tilos'' (fiber) in reference to its iron content and typical fibrous form.[ However, the material at the Idrija location may not be siderotil, but the mineral has been authenticated from a wide variety of worldwide locations.][Handbook of Mineralogy]
/ref>
References
Sulfate minerals
Iron(II) minerals
Triclinic minerals
Minerals in space group 2
Chalcanthite group
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