Aeschynite-(Ce)

 IMA-GP
Thorium
(minor)		 8.3.6.1
(Dana Classification Number)
(No Images) 4/D.21-20
(Strunz ID)

Property Data Remarks
Named for: Its composition, and the Greek word for "shame," due to the inability of the chemists at the time of its discovery to separate its constituent elements.
Alternate
    Name(s):
 
Mineral Class:
Oxides
  Oxides with metal (metal:oxygen = 1:2)
    Aeschynite series
 
Chemical
    Formula:		 (Ce,Ca,Fe,Th)(Ti,Nb)2(O,OH)6 (Solid solution of oxides)
Chemical
    Composition:		 Variable by weight
Molecular
    Weight:		 Variable daltons (amu)
Specific
    Radioactivity:

(All radiation is for a 1 gram, fully aged specimen)

Specific Activity Dose Rate
Becquerels Curies  milliRems 
hour		  microSieverts 
hour
616 1.66 × 10-08 0.01 0.891

Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
Crystalography:
System: Orthorhombic - Dipyramidal
Axial Ratios: a: 0.6882
b: 1
c: 0.494
Cell Dimensions: a: 7.55 Å
b: 10.97 Å
c: 5.42 Å
Z: 4
V: 448.90 Å3
DenCalc: 4.52
H-M Symbol: 2/m 2/m 2/m
Space Group: Pmnb
X-Ray Diffraction:
  By Intensity ( I/Io )		 (1): 2.975 Å
(0.8): 3.024 Å
(0.35): 3.106 Å
Aeschynite-(Ce)
Crystal
Habit:
  • Massive
  • Acicular
    		•   
    Cleavage: None  
    Fracture: Brittle - Conchoidal  
    Moh's
        Hardness:    		 5 - 6  
    Density: 5.19 grams/cm3
    Color: Dark brown  
    Streak: Brownish black  
    Luster: Adamantine - Resinous  
    Diaphaniety: Transparent to Translucent  
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave: Non-fluorescent
    Short Wave: Non-fluorescent
    		 
    Magnetism: Non-magnetic  
    Occurance:
  • Nepheline syenite rocks
    		•   
    Associated
        Minerals:

    Actinolite, Aegirine, Albite, Anatase, Anglesite, Ankerite, ''Apatite', Aragonite, Arsenopyrite, Augite, Barite, Bastnäsite-(Ce), Bertrandite, Beryl, Biotite, Brookite, Calcite, Cerussite, Chalcopyrite, Covellite, Cubanite, Cuprite, Dolomite, Epidote, 'Feldspar', Fluorapatite, Fluorite, Galena, Goethite, Harmotome, Hematite, Ilmenite, Kaolinite, Laumontite, Mackinawite, 'Magnesio-arfvedsonite', Magnetite, Malachite, Marcasite, Microcline, Molybdenite, Monazite-(Ce), Muscovite, Nepheline, Nontronite, Opal, Orthoclase, Phlogopite, Pyrite, Pyrochlore, Quartz, Rhodochrosite, Siderite, Sphalerite, Strontianite, Talc, Thorite, Titanite, 'Wolframite', Wulfenite, Xenotime-(Y), Zircon

    Mineral   -   > 50% of sites
    Mineral   -   > 25% of sites
    Mineral   -   > 15% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Aeschynite-(Ce)
    Localities:

    Rare

    Aeschynite-(Ce) Localities
    Notes:

    Strongly radioactive a- and b-particles, g-rays.

    Crystals are probably metamic.