Bastnasite-(La)

General Information:
 Chemical Formula:
La(CO3)F
 Composition:
(Molecular Weight = 217.91 gm)
Lanthanum 63.74 % La
Carbon 5.51 % C 
Oxygen 22.03 % O 
Fluorine 8.72 % F 
 Empirical Formula:
La(CO3)F
 IMA Status:
Approved IMA 1987
 Locality:
Gallinas Mountains, New Mexico, USA.
 Name Origin:
Named after its locality Bastnas Mine, Riddarhyttan, Vastmanland, Sweden.
Physical Properties:
 Cleavage:
[1011] Imperfect, [0001] Indistinct
 Color:
yellow or reddish brown.
 Density:
4.95 - 5, Average = 4.97
 Diaphaniety:
Transparent to Translucent
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Massive - Granular - Common texture observed in granite and other igneous rock.,
 Hardness:
4-5 - Fluorite-Apatite
 Luster:
Vitreous - Greasy
 Streak:
white
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