Images
Formula: (Na,Ca,☐)BaCe2(CO3)4(F,O)
Anhydrous carbonate containing halogen, cordylite group,
barium- and
cerium- bearing mineral
Specific gravity: 4.31
Hardness: 47#189;
Streak: White
Colour: Colourless, yellowish; colourless to light yellow in transmitted light
Luminescence: No fluorescence under UV
Solubility: Readily soluble in acids
Weakly RADIOACTIVE
Environments:
Localities
At the type locality, the Narssârssuk pegmatite, Narsaarsuk Plateau, Igaliku, Kujalleq, Greenland,
cordylite-(Ce) occurs as prismatic or thin to thick tabular crystals with hexagonal outline in
pegmatitic veins in
nepheline-syenite. Associated minerals include
synchysite-(Ce), neptunite,
ancylite and aegirine
(Mindat).
The Ust'-Biraya, Biraya Fe-REE ore occurrence, Biraya and Bya Rivers confluence area, Vitim
Plateau, Irkutsk Oblast, Russia, comprises a sequence of lens-shaped
carbonatite bodies accompanied by
fenites.
Cordyite-(Ce) occurs in a fine- to medium- grained vein composed mainly of the carbonates
aragonite–strontianite,
emmonite, strontium-rich
calcite, iron-rich
dolomite, cordylite-(Ce) and
cordylite-(La).
Within the vein, cordylite-(Ce) is more common than
cordylite-(La), with only cordylite-(Ce) occurring as
single grains, while cordylite-(La) may occur as cores within
cordylite-(Ce). Also contained in the vein and are baryte,
biraite-(Ce), niobium-rich
chevkinite-(Ce),
fergusonite-(Nd),
ancylite-(Ce), ancylite-(La),
daqingshanite-(Ce),
bastnäsite-(Ce),
hydroxylbastnäsite-(Ce),
carbocernaite,
monazite-(Ce), talc,
thorite, humite,
galena, pyrite and
pyrrhotite. Minerals in the outer zone of the vein near the
fenite include tremolite,
winchite,
ferriallanite-(Ce),
törnebohmite-(Ce),
belkovite, ancylite-(La),
strontianite,
fergusonite-(Ce), zero-valent-dominant light-rare-earth-element
bearing pyrochlore and
nioboaeschynite-(Ce)
(CM 50.5.1281-1290).
Back to Minerals