Idrialite

Idrialite, or Idrialine, is a soft, orthorhombic hydrocarbon mineral, chemical formula: 4[C22 H14]. It is usually greenish yellow to light brown in colour with bluish fluorescence. It can be found mixed with clay, pyrite and gypsum associated with cinnabar in the Idria region, Slovenia. Its combustibility gave rise to the term "inflammable cinnabar", which is one of its synonyms.
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(n.)
A bituminous substance obtained from the mercury mines of Idria, where it occurs mixed with cinnabar.
  

General Information:
 Chemical Formula:
C22H14
 Composition:
(Molecular Weight = 278.35 gm)
Hydrogen 5.07 % H 
Carbon 94.93 % C 
 Empirical Formula:
C22H14
 Environment:
Mercury mine, mixed with cinnabar and clay.
 Locality:
Idria, Slovenia.
 Name Origin:
Named for the locality.
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
greenish yellow, light brown, or colorless.
 Density:
1.236
 Habits:
Tabular - Form dimensions are thin in one direction., ,
 Hardness:
1.5 - Between Talc and Gypsum
 Luminescence:
Fluorescent, Short UV=blue white.
 Luster:
Vitreous - Adamantine
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