Category Organic mineral Strunz classification 10.BA.20 | Formula(repeating unit) C22H14 Dana classification 50.03.08.01 | |
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Crystal system OrthorhombicUnknown space group Unit cell a = 8.07, b = 6.42c = 27.75 [Å]; Z = 4 | ||
Idrialite, or idrialine, is a soft, orthorhombic hydrocarbon mineral with chemical formula: C22H14. It is usually greenish yellow to light brown in color with bluish fluorescence.
Raman spectroscopy studies indicate that it may be a mixture of complex hydrocarbons including benzonaphthothiophenes (chemical formula: C16H10S) and dinaphthothiophenes (chemical formula: C20H12S).
Discovery and occurrence
It was first described in 1832 for an occurrence in the Idrija region west of Ljubljana, northwestern Slovenia. It also occurs at Skaggs Springs, Sonoma County, western Lake County and the Knoxville Mine in Napa County, California. It has also been reported from localities in France, Slovakia and Ukraine.
It can be found mixed with clay, pyrite, quartz and gypsum associated with cinnabar in the Idrija occurrence and with metacinnabar, realgar and opal in the Skaggs Spring location.
Its combustibility gave rise to the term "inflammable cinnabar", which is one of its synonyms.
