Tschermigite is a mineral form of
ammonium alum
Ammonium aluminium sulfate, also known as ammonium alum or just alum (though there are many different substances also called "alum"), is a white crystalline double sulfate usually encountered as the dodecahydrate, formula (NH4)Al(SO4)2·12H2O. It ...
, formula
N H4 Al(
S O4)
2·12(H
2O). It is found in
burning coal seams,
bituminous
Bitumen ( , ) is an immensely viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the m ...
shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny f ...
and
fumarole
A fumarole (or fumerole) is a vent in the surface of the Earth or another rocky planet from which hot volcanic gases and vapors are emitted, without any accompanying liquids or solids. Fumaroles are characteristic of the late stages of volcani ...
s. Because of its extreme water solubility it is unlikely to persist except in the dryest of conditions. Discovered in 1852 at Cermiky, also known as Tschermig in
Bohemia
Bohemia ( ; ; ) is the westernmost and largest historical region of the Czech Republic. In a narrow, geographic sense, it roughly encompasses the territories of present-day Czechia that fall within the Elbe River's drainage basin, but historic ...
. It is colorless and named for where it was discovered.
References
Ammonium minerals
Aluminium minerals
Sulfate minerals
12
Cubic minerals
Minerals in space group 205
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