Uranmicrolite

 IMA-A 1977-SUB
Uranium 8.2.2.4
(Dana Classification Number)
(No Images) 4/C.18-80
(Strunz ID)

Property Data Remarks
Named for: Its Uranium content, and as a member of the microlite group
Alternate
    Name(s):
  • Djalmaite
    		•   
    Mineral Class: Oxides & Hydroxides -
    - Pyrochlore group, Microlite series with Ta > Nb    		  
    Chemical
        Formula:    		 (U,Ca)2(Ta,Nb)2O6(OH)
    or:
    (U,Ca,Ce)2(Ta,Nb)2O(OH,F)    		  
    Chemical
        Composition:
    Calcium: (Ca) 6.91%
    Hydrogen: (H) 0.14%
    Niobium: (Nb) 2.67%
    Oxygen: (O) 16.10%
    Tantalum: (Ta) 46.81%
    Uranium: (U) 27.37%
    		by weight
    Molecular
        Weight:    		 695.81 daltons (amu)
    Specific
        Radioactivity:

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

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    4.8987 × 1004 1.32 × 10-06 0.65 64.85

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Isometric - Hexoctahedral
    Axial Ratios: a:b:c = ::
    Cell Dimensions: a = 10.4, Z = 6; V = 1,124.86 Den(Calc) = 6.16
    H-M Symbol: 4/m -3 2/m
    Space Group: Fd3m
    X Ray Diffraction: By Intensity(I/Io): 1.552(1) 1.818(1) 2.95(1) 0.995(0.8) 1.054(0.8) 1.154(0.8) 1.183(0.8) 2.55(0.8)
    		 
    Habit:
  • Octahedral Crystals
  		•   
    Cleavage: None  
    Fracture: Uneven  
    Moh's
        Hardness:    		 5.5  
    Density: 5.75 - 5.88 grams/cm3
    Color: Yellowish brown, Greenish-brown, Brownish-black, Black  
    Streak: Yellow, Grey-white  
    Luster: Greasy  
    Diaphaneity: Transparent to Opaque  
    Pleochroism:
    (x):
    (y:)
    (z:)
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:
    Short Wave:
    		 
    Magnetism: Non-magnetic  
    Occurance:
  		•  
    Associated
        Minerals:

    Albite, Beryl, Biotite, Bismuth, Bismuthinite, Elbaite, Eosphorite, Ferrocolumbite, Ferrotantalite, Ferrotapiolite, Fluorapatite, Fluorite, Kaolinite, Lepidolite, Manganocolumbite, Manganotantalite, Microcline, Microlite, 'Monazite', Muscovite, Quartz, Rutile var: Strüverite, Samarskite, Schorl, Spessartine, Triplite, Uraninite, Zircon

    Mineral   -   > 75% of sites
    Mineral   -   > 50% of sites
    Mineral   -   > 25% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Uranmicrolite
    Locations:

    Rare

    Uranmicrolite Locations
    Notes:

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

    Crystals are probably metamic.