Mineral - Bastnäsite-(Ce)
Bastnäsite-(Ce)
Chemical Properties
Mineral Class
Carbonates
Toxicity
none
Formula
Ce(CO₃)F
Unit Cell
a=7.12 c=9.76 Z=6
Physical Properties
Hardness
4.5
Streak
white
Density
Heavy (3,5-6)
Cleavage
Indistinct after {10 1 0}
Fracture
uneven
Tenacity
Brittle
Optical Properties
Color
brownredorangeyellowcolorless
Birefringence
0.101
Luster
Vitreous,
Greasy
Transparency
translucent,
transparent
Pleochroism
Schwach
Geomineralogical Properties
Crystal System
hexagonal
Point Group
ditrigonal-dipyramidal - 6 m2
Space Group
P 6 c2 (188)
Habit
blocky, granular, prismatic
Formation
Magmatic, in plutonites (also carbonatites) and their pegmatites, sedimentary in alluvial placer deposits
Paragenesis
Twinning
Rarity
Common
Synonyms
Bastnäsite-(Ce), Bastnäsite
Composition
Elements
Mass
P₂O₅
0.60
CO₂
20.20
La₂O₃
36.30
Ce₂O₃
40.50
F
6.23
Madagascar (Palache et al. 1952)
Groups and Members
Bastnäsite-Group
Name and first discovery: Named after the type locality, the Bastnäs Mines in Sweden. First described in 1841.
Chemism:
Synonyms: Buszite, kishtimite, hydrofluocerite, hamartite, hydrocerite, cercarbonate, basic fluorocerium
Varieties:
Abbreviation: Bsn-Ce
Literature
Palache, C., Berman, H., & Frondel, C. (1952). Dana's system of mineralogy. GeologiskaFöreningen i Stockholm Förhandlingar, 74(2), 218-219.