Outstanding pale beige crystals of the extremely rare thorium mineral tuliokite from the type and only known locality in Khibiny: Kirovskii Mine, Kukisvumchorr Mountain, Khibiny Massif, Murmansk Oblast, Russian Federation. Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Tuliokite
Tuliokite is an IMA-recognized mineral species in the carbonate class, with the chemical formula Na₆BaTh(CO₃)₆·6H₂O.
It crystallizes in the hexagonal crystal system (space group R-3).
Key properties: Mohs hardness 3–4; specific gravity 3.15; White streak; Vitreous luster; optically uniaxial.
IMA symbol Tli, IMA status: approved, named in 1988.
Found in hydrothermal veins in nepheline syenite pegmatite.
It is found associated with Sidorenkite, vinogradovite, villiaumite, microcline (vein 1); pirssonite, shortite, trona, thermonatrite, natron, villiaumite, natrolite, aegirine.
The name refers to the Tuliok River, Kola Peninsula, Russia, near where the mineral was first found.