Plumbopyrochlore

 IMA-A 1977-SUB
Uranium 8.2.1.6
(Dana Classification Number)
(No Images) 4/C.17-80
(Strunz ID)

Property Data Remarks
Named for: Its Lead (Plumbum) content, and its relationship to pyrochlore
Alternate
    Name(s):
  		•  
    Mineral Class:
    Oxides
      Oxides with metal: (metal:oxygen = 2:3)
    (M2O3 and related compounds)
      Pyrochlore group
          Pyrochlore series with Nb > Ti
    		 
    Chemical
        Formula:    		 (Pb,Y,U,Ca)2-xNb2O6(OH)  
    Chemical
        Composition:
    Calcium: (Ca) 0.83%
    Hydrogen: (H) 0.10%
    Iron: (Fe) 2.31%
    Lead: (Pb) 34.25%
    Niobium: (Nb) 26.87%
    Oxygen: (O) 22.15%
    Silicon: (Si) 1.16%
    Tantalum: (Ta) 3.74%
    Yttrium: (Y) 3.67%
    Uranium: (U) 4.92%
    		by weight
    Molecular
        Weight:    		 484.00 daltons (amu)
    Specific
        Radioactivity:

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

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    8.803 × 1003 2.38 × 10-07 0.12 12.04

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Isometric - Hexoctahedral
    Cell Dimensions: a: 10.534 Å
    Z: 8
    V: 1,168.91 Å3
    DenCalc: 5.50
    H-M Symbol: 4/m -3 2/m
    Space Group: Fd3m
    X-Ray Diffraction:
      By Intensity ( I/Io )    		 (1): 3.02 Å
    (0.9): 1.581 Å
    (0.9): 1.861 Å
    		 
    Habit:
  • Octahedral Crystals
    		•   
    Cleavage: None  
    Fracture: Brittle - Uneven  
    Moh's
        Hardness:    		 4.5 - 5.5  
    Density: 5.04 grams/cm3
    Color: Reddish yellow, Brown  
    Streak:    
    Luster: Vitreous - Resinous  
    Diaphaneity: Translucent to Opaque  
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:  
    Short Wave:  
    		 
    Magnetism: Non-magnetic  
    Occurance:
  • Metasomatically altered granitic rocks
    		•   
    Associated
        Minerals:

    Albite, Bastnäsite-(Ce), Bertrandite, Cassiterite, 'Columbite', Cryolite, Elpasolite, Fluorite, Genthelvite, Hematite, Hingganite-(Y), Ilmenite, Manganocolumbite, Microcline, Microcline var: Amazonite, Microlite, Muscovite, Pachnolite, Phenakite, Prosopite, Quartz, Quartz var: Smoky Quartz, Ralstonite, Thomsenolite, Thorite, Topaz, Weberite, Xenotime-(Y), Zinnwaldite, Zircon

    Mineral   -   > 60% of sites
    Mineral   -   > 40% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Plumbopyrochlore
    Locations:

    Rare

    Plumbopyrochlore Locations
    Notes:

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

    Crystals may be metamict.