Bayleyite

 IMA-GP
Uranium 15.3.3.1
(Dana Classification Number)
(Images) 5/F.02-20
(Strunz ID)

Property Data Remarks
Named for: William S. Bayley (1861-1943, Professor of geology, University of Illinois & geologist for the U.S. Geological Survey
Alternate
    Name(s):
 
Mineral Class:
Nitrates, Carbonates and Borates
  Uranylcarbonates ([UO2]+2 - [CO3]-2)
    Grimselite - Liebigite series
 
Chemical
    Formula:		 Mg2(UO2)(CO3)3 · 18H2O  
Chemical
    Composition:
Carbon: (C) 4.38%
Hydrogen: (H) 4.41%
Magnesium: (Mg) 5.91%
Oxygen: (O) 56.38%
Uranium: (U) 28.92%
by weight
Molecular
    Weight:		 822.94 daltons (amu)
Specific
    Radioactivity:

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

Specific Activity Dose Rate
Becquerels Curies milliRADs
per hour		 microSieverts
5.1774 × 1004 1.40 × 10-06 0.79 7.92

Estimated Average Annual Exposure: 3.6 RAD (3.6 centiSieverts)
Crystalography:
System: Monoclinic - Prismatic
Axial Ratios: a: 1.7406
b: 1
c: 0.4265
Cell Dimensions: a: 26.65 Å
b: 15.31 Å
c: 6.53 Å
Z: 4
b: 93.066°
V: 2,660.50 Å3
DenCalc: 2.05
H-M Symbol: 2/m
Space Group: P21/a
X-Ray Diffraction:
  By Intensity ( I/Io )		 (1): 7.66 Å
(0.9): 13.1 Å
(0.6): 3.83 Å
 
Habit:
  • Short prismatic crystals up to 3 mm length
  • Crusts
    		•   
    Cleavage: None  
    Fracture: Conchoidal.  
    Moh's
        Hardness:    		    
    Density: 2.05 grams/cm3
    Color: White to light Yellow, Pale yellow with slight Greenish hue to Pale Green with slight yellowish hue  
    Streak: White  
    Luster: Vitreous - Earthy  
    Diaphaneity: Transparent to translucent  
    Pleochroism:
    (x): Colorless
    (y:) Colorless
    (z:) Colorless
    		 
    Ultra Violet
        Fluorescence:
    Long Wave: Pale Green
    Short Wave: Pale Green
    		(Short wave somewhat stronger)

    (One Specimen Examined)
    Magnetism: Non-magnetic  
    Occurance:
  • Oxidation zone in uranium deposits
    		•   
    Associated
        Minerals:

    Andersonite, Aragonite, Autunite, Azurite, Barite, Bournonite, Calcite, Cerussite, Chalcopyrite, Dickite, Dolomite, Epsomite, Fluorite, Galena, Goethite, Gypsum, Hematite, Ilsemannite, Jarosite, Johannite, Kaolinite, Lepidocrocite, Malachite, Marcasite, Metatorbernite, Molybdenite, Muscovite, Novácekite, Pyrite, Quartz, Saléeite, Sphalerite, Sulphur, Tetrahedrite, Torbernite, Uraninite, Uranopilite, Zeunerite, Zippeite

    Mineral   -   > 50% of sites
    Mineral   -   > 25% of sites
    Mineral   -   > 15% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Bayleyite
    Localities:

    Rare

    Bayleyite Localities
    Notes:

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

    Crystals are probably metamic.

    Bayleyite Images

    Specimen Top
    (001a) (001b) (001c) (001d)
    (001e) (001elw) (001esw)

    (Long Wave Ultraviolet)
    (Short Wave Ultraviolet)
    Hideout #1 mine, White Canyon district, San Juan Co., Utah, U.S.A.


    Specimen Notes

    Fluorescence - The fluorescence of Bayleyite is strong, and a pale green color. This color is washed out in the two images above by the ultraviolet light. In the right hand image this color can just be seen in places. The fluorescence is nearly equal in intensity and color in both long and short wave ultraviolet light.

    Formation - The Bayleyite forms on an Aragonite substrate on silicate host rock. The Bayleyite crystals appear to only form on a substrate of Aragonite, and does not form directly on the silicate host rock.

    Crystal Form - Bayleyite crystals form as flat, square ended leaves, triangular dagger blades, and tappered needles. All of these forms are intermixed with no apparent causality as to which form occurs where.

    The crystals form in open radial clusters. The needle shaped crystals are most likely to form in well shaped clusters, sometimes with dagger shaped crystals in close association. The broad, square ended, leaves usually occur as individuals. Crystals that are broad leaves at their base and narrow down into broad daggers will usually occur in clusters of other, narrow, dagger shaped crystals.

    Fluorescence - The fluorescence is strong in both long and short wave ultraviolet light. This fluorescence is approximately the color of water starved grass.