Weeksite

 IMA-GP
Uranium 53.3.2.1
(Dana Classification Number)
(Images) 8/H.37-10
(Strunz ID)

Property Data Remarks
Named for: Dr. Alice D. Weeks, U.S. Geological Survey
Alternate
    Name(s):
  • Gastunite
    		•   
    Mineral Class:
    Silicates
      Phyllosilicates, with simple layers [Si6O15]-6, and others
        Weeksite series
    		 
    Chemical
        Formula:    		 K2[(UO2)2(Si5O13)] · 1.4(H2O)  
    Chemical
        Composition:
    Barium: (Ba) 4.00%
    Calcium: (Ca) 0.39%
    Hydrogen: (H) 0.27%
    Oxygen: (O) 28.92%
    Potassium: (K) 4.18%
    Silicon: (Si) 13.65%
    Uranium: (U) 48.58%
    		by weight
    Molecular
        Weight:    		 1028.91 daltons (amu)
    Specific
        Radioactivity:

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

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    8.6962 × 1004 2.35 × 10-06 1.20 120.28

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Orthorhombic - Dipyramidal,
    or Pseudotetragonal
    Axial Ratios: a:b:c = 0.9972:1:2.5174
    Cell Dimensions: a = 14.209, b = 14.248, c = 35.869, Z = 16; V = 7,261.67 Den(Calc) = 3.76
    H-M Symbol: 2/m 2/m 2/m
    Space Group: Cmmb or Pnnb
    X Ray Diffraction: By Intensity(I/Io): 7.11(1) 5.57(0.9) 8.98(0.8)
    		 
    Habit:
  • radiating crystals
  • Crystals elongated on the c-axis
  • crystals sometimes bladed
    		•   
    Cleavage:
    [001]
    [010]
    [100]
    		 
    Fracture:    
    Moh's
        Hardness:    		 1 - 2  
    Density: 4.1 grams/cm3
    Color: Bright yellow  
    Streak: Yellow  
    Luster: Waxy to Silky  
    Diaphaneity: Transparent to Translucent  
    Pleochroism:
    X (b): Colorless
    Y (c): Pale yellow-green
    Z (a): Yellow-green
    		 
    Ultra Violet
        Fluorescence:    		 Non-Fluorescent (One Specimen Examined)
    Magnetism: Non-magnetic  
    Occurance:
  • Hydrothermal deposits in ryolite and agglomerates
  • Sandstone
  • Limestone
    		•   
    Associated
        Minerals:

    Autunite, 'Barite', Becquerelite, Calcite, Carnotite, Chalcocite, Chalcopyrite, Chrysocolla, Coffinite, Cuprosklodowskite, Dolomite, Fluorite, Galena, Goethite, Hematite, Jarosite, Johannite, Kasolite, Liebigite, Malachite, Marcasite, Meta-Autunite, Metatorbernite, Metatyuyamunite, Molybdenite, Muscovite, Novácekite, Phosphuranylite, Pyrite, Pyrolusite, Quartz, Roscoelite, Schoepite, Sklodowskite, Soddyite, Sodium-Zippeite, Sphalerite, Torbernite, Tyuyamunite, Uraninite, Uranophane, Uranophane-beta, Uranopilite, Wulfenite, Zippeite

    Mineral   -   > 69% of sites
    Mineral   -   > 46% of sites
    Mineral   -   > 23% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Weeksite
    Locations:

    Very rare

    Weeksite Locations
    Notes:

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

    Weeksite Images

    Specimen #1
    (001)
    (001a) (001b) (001c)
    (All the above)
    Jackpile Mine, Laguna District, Cibola Co., New Mexico, USA


    Specimen Notes

    Occurrence -  

     

      -  

     

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