Steenstrupine-(Ce)

 IMA-GP
Thorium  
(Dana Classification Number)
(Images) 8/E.17-10
(Strunz ID)

Property Data Remarks
Named for: Knud Hohannes Vogelius Steenstrup (1842-1913), geologist, Copenhagen, Denmark
Alternate
    Name(s):
  • Steenstrupine
  • Steenstrupite
    		•   
    Mineral Class:
    Silicates
      Cyclosilicates
    rings of six tetrahedrons [Si6O18]-12
        Steenstrupine-(Ce) series
    		 
    Chemical
        Formula:    		 Na14Ce6Mn2+Mn3+Fe2+2(Zr,Th)(Si6O18)2(PO4)7 · 3H2O  
    Chemical
        Composition:
    Cerium: (Ce) 26.75%
    Hydrogen: (H) 0.19%
    Iron: (Fe) 3.55%
    Manganese: (Mn) 3.50%
    Oxygen: (O) 34.11%
    Phosphorus: (P) 6.90%
    Silicon: (Si) 10.73%
    Sodium: (Na) 10.24%
    Thorium: (Th) 1.85%
    Zirconium: (Zr) 2.18%
    		by weight
    Molecular
        Weight:    		 3,142.39 daltons (amu)
    Specific
        Radioactivity:

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

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    827 2.24 × 10-08 0.01 1.21

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Trigonal - Hexagonal Scalenohedral
    Axial Ratios: a: 1
    c: 4.34789
    Cell Dimensions: a: 10.46 Å
    c: 45.479 Å
    Z: 3
    V: 4,309.28 Å3
    DenCalc: 3.63
    H-M Symbol: -3 2/m
    Space Group: R-3m
    X-Ray Diffraction:
      By Intensity ( I/Io )    		 (1): 2.87 Å
    (1): 3.09 Å
    (0.7): 4.2 Å
    		 
    Habit:
  • Blocky
  • Prismatic
    		•   
    Cleavage: None  
    Fracture: Conchoidal  
    Moh's
        Hardness:    		 4  
    Density: 3.4 grams/cm3
    Color: Brownish black  
    Streak: Tan  
    Luster: Sub-metallic  
    Diaphaneity: Opaque  
    Dichroism:
    (e): Yellow Brown
    (w:) Dark Brown
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:  
    Short Wave:  
    		 
    Magnetism: Non-magnetic  
    Occurance:
  • Associated with ultra-agpaitic pegmatites of nepheline syenites and sodalite syenites
    		•   
    Associated
        Minerals:

    Aegirine, Albite, Analcime, Belovite, Cancrinite, Chkalovite, Dorfmanite, Epididymite, Epistolite, Eudialyte, Fluorite, Galena, Gerasimovskite, Labuntsovite, Lamprophyllite, Leucosphenite, Lomonosovite, Lorenzenite, Lovdarite, Lovozerite, 'Mangan-Neptunite', Manganonordite-(Ce), Microcline, Molybdenite, Murmanite, Narsarsukite, Natrolite, Natrophosphate, Nenadkevichite, Nepheline, Neptunite, Nordite-(Ce), Pectolite, Penkvilksite, Phosinaite-(Ce), Polylithionite, Quartz, Raite, Rasvumite, Rhabdophane-(Ce), Sazhinite-(Ce), Serandite, Shafranovskite, Sodalite, Sphalerite, Terskite, Tetranatrolite, Thermonatrite, Tugtupite, Ussingite, Villiaumite, Vitusite-(Ce), Vuonnemite, Zakharovite

    Mineral   -   > 60% of sites
    Mineral   -   > 50% of sites
    Mineral   -   > 25% of sites
    Minerals   -   Uranium & Thorium
    mineral links

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

    Rare

    Steenstrupine-(Ce) Locations
    Notes:

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

    Crystals are probably metamic.

    Steenstrupine-(Ce) Images

    Specimen #1
    (001aa)
    Kvanefield, Ilimanssaq, Greenland

    Specimen Notes

    Occurrence -  

     

    Crystals -  

     

    Appearence -  

    Diaphaniety -

    Luster -

     

      -  

     

    Specimen Physical Properties
    Size   cm   cm   cm
    Weight: x grams    
    g-Radiation Level:   cmp   msieverts background: 20 cpm