Fichtelite is a rare white mineral found in fossilized wood from Bavaria. It crystallizes in the monoclinic crystal system. It is a cyclic hydrocarbon: dimethyl-isopropyl-perhydrophenanthrene, C19H34. It is very soft with a Mohs hardness of 1, the same as talc. Its specific gravity is very low at 1.032, just slightly denser than water.

Fichtelite
Chemical structure of fichtelite
General
CategoryOrganic mineral
Formula
(repeating unit)
C19H34
IMA symbolFic[1]
Strunz classification10.BA.05
Hydrocarbons
Dana classification50.03.04.01
Crystal systemMonoclinic
Crystal classSphenoidal (2)
(same H-M symbol)
Space groupP21
Identification
ColorColorless, white, pale yellow
Crystal habitElongated tabular crystals
CleavageGood on {001} and {100}
Mohs scale hardness1
LusterGreasy
StreakWhite
DiaphaneityTransparent
Specific gravity0.631 calculated[2] 1.032[3]
Optical propertiesBiaxial
Melting point44.2 °C – 45.0 °C
References[2][3][4]

It was first described in 1841 and named for the location, Fichtelgebirge, Bavaria, Germany.[4] It has been reported from fossilized pine wood from a peat bog and in organic-rich modern marine sediments.[2]

References

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  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ a b c http://rruff.geo.arizona.edu/doclib/hom/fichtelite.pdf Handbook of Mineralogy
  3. ^ a b http://webmineral.com/data/Fichtelite.shtml Webmineral data
  4. ^ a b http://www.mindat.org/min-1545.html Mindat.org