Ancylite-(La)

 IMA-1995-053
Uranium
(trace)		 16b.1.1.5
(Dana Classification Number)
(No Images) 5/E.08-28
(Strunz ID)

Property Data Remarks
Named for: its composition, and the Greek word for "curved," in allusion to the rounded and distorted character of its crystals.
Alternate
    Name(s):
 
Mineral Class:
Nitrates, Carbonates and Borates
  Water-bearing carbonates
    Strontiodresserite - Dundasite series
 
Chemical
    Formula:		 Sr(La,Ce)(CO3)2(OH) · H2O  
Chemical
    Composition:
Carbon: (C) 6.29%
Cerium: (Ce) 9.17%
Hydrogen: (H) 0.79%
Lanthanum: (La) 27.28%
Oxygen: (O) 33.52%
Strontium: (Sr) 22.95%
Uranium: (U) (trace)
by weight
Molecular
    Weight:		 381.87 daltons (amu)
Specific
    Radioactivity:

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

Specific Activity Dose Rate
Becquerels Curies  milliRems 
hour		  microSieverts 
hour
817 2.21 × 10-08 0.01 1.17

Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
Crystalography:
System: Orthorhombic - Dipyramidal
Axial Ratios: a: 0.5905
b: 1
c: 0.8471
Cell Dimensions: a: 5.072 Å
b: 8.589 Å
c: 7.276 Å
Z: 2
V: 316.97 Å3
DenCalc: 4.00
H-M Symbol: 2/m 2/m 2/m
Space Group: Pmcn
X-Ray Diffraction:
  By Intensity ( I/Io )		 (1): 2.955 Å
(0.92): 4.36 Å
(0.9): 3.705 Å
 
Habit:
  • Pyramidal crystals
  • Fine crystals
    		•   
    Cleavage: None  
    Fracture: Brittle  
    Moh's
        Hardness:    		 4 - 4.5  
    Density: 3.88 grams/cm3
    Color: Light Yellow, Yellowish-brown  
    Streak: White  
    Luster: Vitreous - Glassy  
    Diaphaniety: Translucent  
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:  
    Short Wave:  
    		 
    Magnetism: Non-magnetic  
    Occurance:
  • In hydrothermal veins in nepheline syenites
    		•   
    Associated
        Minerals:

    Aegirine, Albite, Analcime, Ancylite-(Ce), 'Apatite', Aragonite, Arfvedsonite, Arsenopyrite, Astrophyllite, Carbonate-fluorapatite, Catapleiite, Cerussite, 'Chabazite', Cryolite, Cryptomelane, Dolomite, Donnayite-(Y), Elpidite, Epididymite, Eudialyte, Fluorite, Gaidonnayite, Galena, Gibbsite, 'Gmelinite Series', Goethite, Gonnardite, Gypsum, Hematite, Hilairite, Ilmenite, Kaolinite, Labuntsovite-Mn, Lorenzenite, Lĺvenite, Löllingite, Makatite, 'Mangan-neptunite', Marcasite, Microcline, Monazite-(Ce), Montmorillonite, 'Mosandrite', Muscovite, Natrolite, Nenadkevichite, Nepheline, Opal, Orthoclase, Paranatrolite, Pectolite, Polylithionite, Pyrite, Rhabdophane-(Ce), Rhodochrosite, Rinkite, Siderite, 'Smectite Group', Strontianite, Sérandite, Thomsonite, Titanite, Todorokite, Villiaumite, Vuonnemite, Wulfenite, Zakharovite, Zircon

    Mineral   -   > 60% of sites
    Mineral   -   > 80% of sites
    Mineral   -   > 100% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Ancylite-(La)
    Localities:

    Rare

    Ancylite-(La) Localities
    Notes:

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

    Crystals are probably metamic.