Vicanite-(Ce)

 IMA-A 1991-050
Thorium 54.3.1.1
(Dana Classification Number)
(No Images) 8/B.33-25
(Strunz ID)

Property Data Remarks
Named for: Vican (Vico lake) volcanic complex at Tre Croci, Ventralla (north of Rome), Latium, Veterbo provicne, Italy
Alternate
    Name(s):
  		•  
    Mineral Class:
    Silicates
      Nesosilicates, with
    anions unfamiliar to tetraheders,
    with beryllium and boron
        Melanocerite-(Ce) - Tritomite-(Ce) series
    		 
    Chemical
        Formula:    		 (Ca,Ce,La,Th)15As+5(As+30.5,Na0.5)Fe+3Si6B4O40F7  
    Chemical
        Composition:
    Arsenic: (As) 4.40%
    Boron: (B) 1.69%
    Calcium: (Ca) 12.55%
    Cerium: (Ce) 19.20%
    Fluorine: (F) 5.21%
    Iron: (Fe) 2.19%
    Lanthanum: (La) 13.59%
    Oxygen: (O) 25.05%
    Silicon: (Si) 6.60%
    Sodium: (Na) 0.45%
    Thorium: (Th) 9.08%
    		by weight
    Molecular
        Weight:    		 2,554.77 daltons (amu)
    Specific
        Radioactivity:

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

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    4.069 × 1003 1.10 × 10-07 0.06 5.80

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Trigonal - Ditrigonal Pyramidal
    Axial Ratios: a:c = 1:2.53228
    Cell Dimensions: a = 10.795, c = 27.336, Z = 3; V = 2,758.74 Den(Calc) = 4.61
    H-M Symbol: 3m
    Space Group: R3m
    X Ray Diffraction: By Intensity(I/Io): 2.993(1) 2.95(0.7) 7.7(0.5)
    		 
    Habit:
  • Anhedral Grains
  • Crystalline - Fine
    		•   
    Cleavage: None  
    Fracture: Conchoidal  
    Moh's
        Hardness:    		 5 - 5.5 - 6  
    Density: 4.73 grams/cm3
    Color: Yellow, Yellowish green, Green  
    Streak: White  
    Luster: Vitreous - Adamantine  
    Diaphaneity: Transparent  
    Pleochroism:
    (e:) Colorless
    (w:) Colorless
    		 
    Ultra Violet
        Fluorescence:    		 Non-fluorescent  
    Magnetism: Non-magnetic  
    Occurance:
  • Inside a volcanic ejectum from a pyroclastic formation
  		•   
    Associated
        Minerals:

    'Aegirine-augite', Afghanite, Allanite-(Ce), Analcime, Anatase, Andradite var: Melanite, Anorthite, Asbecasite, Augite, Baddeleyite, 'Barite', Betafite, Biotite, Britholite-(Y), Calciobetafite, Calcite, Cancrinite, Ciprianiite, Clinohumite, Corundum, Cristobalite, Cryptomelane, Danburite, Davyne, Diopside, Ekanite, Epidote, 'Ferrierite', Ferrohornblende, Fluorapatite, Fluorite, Forsterite, Gadolinite-(Ce), Goethite, Grossular, Gypsum, Haüyne, 'Hellandite', 'Hellandite-(Y)', Helvite, Hematite, 'Heulandite', 'Kennedyite', Leucite, Magnetite, Molybdenite, Monazite-(Ce), Nepheline, Nosean, Osumilite-(Mg), Peprossiite-(Ce), Perovskite, 'Phillipsite', Phlogopite, Pseudobrookite, Pyrite, Pyrope, Quartz, Rutile, Sanidine, 'Scapolite', Scheelite, Sodalite, Spinel, 'Stilbite', Stillwellite-(Ce), Stoppaniite, Thorite, Uranothorite, Titanite, 'Tourmaline Group', Tridymite, Uraninite, Uranpyrochlore, Vesuvianite, Vonsenite, Zircon, Zirconolite

    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Vicanite-(Ce)
    Locations:

    Extremely rare

    Vicanite-(Ce) Locations
    Notes:

    Radioactive a- and b-particles, g-rays.

    Crystals are probably metamic.