Chistyakovaite

 IMA-2005-003
Uranium  
(Dana Classification Number)
(Images)  
(Strunz ID)

  All information confirmed from IMA announcement  

Property Data Remarks
Named for:  
Alternate
    Name(s):
 
Mineral Class:
 
   
     
 
Chemical
    Formula:		 Al(UO2)(AsO4)2(F,OH) · 6.5H2O  
Chemical
    Composition:
xxx: (x) %
xxx: (x) %
xxx: (x) %
Uranium: (U) %
by weight
Molecular
    Weight:		   daltons (amu)
Specific
    Radioactivity:

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

Specific Activity Dose Rate
Becquerels Curies  milliRems 
hour		  microSieverts 
hour
× 100 × 10-0    

Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
Crystalography:
System: Monoclinic
Axial Ratios: a: 2.04188
b: 1
c: 2.00409
Cell Dimensions: a: 19.99 Å
b: 9.79 Å
c: 19.62 Å
Z:  
b: 110.7°
V:   Å3
DenCalc:  
H-M Symbol:  
Space Group: P2/m, P2 or Pm
X-Ray Diffraction:
  By Intensity ( I/Io )		 (1): 9.34 Å
(1): 9.14 Å
(0.27): 4.76 Å
(0.20): 4.87 Å
(0.18): 4.93 Å
(0.17): 4.69 Å
(0.15): 3.55 Å
(0.13): 2.281 Å
Chistyakovaite
Crystal
(Observed)
Habit:
  • Small, flat, lath-like, bladed crystals
  		•  Tony Nikischer
    Cleavage:
    [001]  
    [010]  
    [100]  
    		 
    Fracture:    
    Moh's
        Hardness:    		    
    Density:   grams/cm3
    Color: pale Yellow, pale Greenish-yellow Tony Nikischer
    (observed)
    Streak:    
    Luster: Vitreous  
    Diaphaniety: Transparent Tony Nikischer
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave: Weak Yellow with greenish tint
    Short Wave: Weak Yellow with greenish tint
    Fluorescence is primarily along edges.    		 (One Specimen Examined)
    Magnetism: Non-magnetic  
    Occurance:
  • In a felsic porphory.
    		•   
    Associated
        Minerals:

    Arseniosiderite, Arsenopyrite, Bearsite, Beryl, Calcite, Conichalcite, Galena, Mansfieldite, Metazeunerite, Molybdenite, Orpiment, Pharmacosiderite, Pyrite, Quartz, Realgar, Scorodite, 'Sodium Uranospinite', Sphalerite, Strakhovite, Strelkinite, Tyrolite, Uraninite

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

    		These are minerals known to be found with Chistyakovaite
    Localities:

    Rare

    Chistyakovaite Localities

    Uranium Deposit, Bota-Burum, Kazakhstan (type locale)
    Notes:

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

    Related to threadgoldite.

    Crystals are probably metamic.

    Chistyakovaite Images

    Specimen #1
    (001a) (001b) (001c)
    Bota-Burum U deposit, Alakol' Lake, Chu-Ili Mts, Zhezqazghan Oblysy (Dzezkazgan Oblast'; Dzhezkazgan Oblast'; Djezkazgan Oblast'; Jezkazgan Oblast'), Kazakhstan (type locale)

    Specimen Notes

    Occurrence - The specimen is reported to have been found in a felsic porphyry host rock. No remnant of this matrix is with the specimen.

    Due to the specime's diminutive size, a 2X auxiliary lens was used in conjuction with the microscope's 30X objective. The result is a grainy image, for which I appologize. By eye, the crystals appear as in the three dimensional model, except for color.

    Crystals - The crystals are archtypical monoclinic in form. This is best seen in image (001a). There appears to be some slight markings on the {001} plane in the direction of the (100) axis.

    The crystals appear to have their (001) axis aligned to each other. The (010) and (100) axes are also aligned, but one crystal may have these axes cross-aligned to the other crystals.

    Appearence -  

    Diaphaniety - The crystals are transparent, but may be translucent in millimeter sized crystals.

    Luster - The luster appears to be vitreous to adamantine.

    Color - The crystals have a pale yellow color with a greenish tint. This tint is seen better in the thicker areas of the specimen.

    Fluorescence - The specimen fluoresces weakly under both long and short wave ultraviolet light a yellow with a somewhat greenish tint. The fluorescence is strongest along the corner edges of the crystals, and a little weaker on surface markings. The crystal body does fluoresce, but much more weakly than these edges.

      -  

     


    Special Notes
    The specimen is reported to be a fragment from the type specimen. The discovery was made in a museum type specimen for another mineral likely at either the Russian Academy of Sciences in Moscow or perhaps from the Fersman Museum.

    Specimen Physical Properties
    (The specimen is too small to accurately character)
    Size ~ 0.02 cm ~ 0.015 cm ~ 0.003 cm
    Weight: milligrams   (specimen too small to accurately measure)
    g-Radiation Level: (specimen too small to accurately measure)   msieverts background: 20 cpm