Aeschynite-(Ce)

Aeschynite-(Ce) (or Aschynite, Eschinite, Eschynite) (Ce,Ca,Fe,Th)(Ti,Nb)2(O,OH)6 is a mineral of cerium, calcium, iron, thorium, titanium, niobium, oxygen, and hydrogen. Its name comes from the Greek word for "shame". Its Mohs scale rating is 5 to 6.
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General Information:
 Chemical Formula:
(Ce,Ca,Fe)(Ti,Nb)2(O,OH)6
 Composition:
(Molecular Weight = 305.70 gm)
Calcium 3.93 % Ca
Cerium 27.50 % Ce
Titanium 27.41 % Ti
Niobium 7.60 % Nb
Iron 1.83 % Fe
Hydrogen 0.33 % H 
Oxygen 31.40 % O 
 Empirical Formula:
Ce0.6Ca0.3Fe2+0.1Ti1.75Nb0.25O5(OH)
 Environment:
Nepheline syenite rocks.
 IMA Status:
Approved IMA 1987
 Locality:
TL: Russia, Chelyabinsk, Il'men Mountians.
 Name Origin:
Named for its composition and from the Greek for "shame," in allusion to the inability of chemists, at the time of its discovery, to separate some of its constituents.
Physical Properties:
 Cleavage:
None
 Color:
brown, brownish black, yellow, or black.
 Density:
5.19
 Diaphaniety:
Transparent to translucent
 Habits:
Massive - Uniformly indistinguishable crystals forming large masses., Acicular - Occurs as needle-like crystals.,
 Hardness:
5-6 - Between Apatite and Orthoclase
 Luminescence:
Non-fluorescent.
 Luster:
Adamantine - Resinous
 Streak:
brownish black
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