Pale brown crystals of the extremely rare mineral vyuntspakhkite-(Y) from one of the only three localities known worldwide: Evans Lou Mine, Lac Saint Pierre, Québec, Canada. Vyuntspakhkite-(Y) is a silicate of ittrium and ytterbium, and is one of the only 5 mineral species (from more than 5500 species known) that contain the chemical element ytterbium (source MINDAT), so it is a real chemical rarity. — Photo: David Hospital · CC BY-SA 4.0
Vyuntspakhkite-(Y)
Vyuntspakhkite-(Y) is an IMA-recognized mineral species in the silicate class, with the chemical formula Y(Al,Si)(SiO₄)(OH,O)₂.
It crystallizes in the monoclinic crystal system (space group P2_1/n).
Key properties: Mohs hardness 6–7; specific gravity 4.02; Adamantine luster; optically biaxial.
IMA symbol Vyu-Y, IMA status: approved, named in 1982.
Two generations of crystals occur in fluorite in \amazonite" pegmatites.
It is found associated with Fluorite, gadolinite, xenotime, bastnÄa site (Mt. Ploskaya, Russia).
The name refers to Mt. Vyuntspakhk, 5 km southeast of Mt. Ploskaya, Kola Peninsula, Russia, and its yttrium content.