Taseqite
A strontium-rich eudialyte-group mineral from Greenland's Ilimaussaq complex.
Intro adapted from Wikipedia (CC BY-SA).
Taseqite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₁₂Sr₃Ca₆Fe₃Zr₃NbSi₂₅O₇₃(O,OH,H₂O)₃Cl₂.
It crystallizes in the hexagonal crystal system (space group R3m). It is a member of the Eudialyte structural group.
Key properties: Mohs hardness 5.5; specific gravity 3.24; White to light brown streak; Vitreous luster; optically uniaxial.
IMA symbol Tsq, IMA status: approved, named in 2002.
Found in a cavity in a late-stage hydrothermal albitite vein in alkaline igneous complex.
It is found associated with Albite, aegirine, analcime, ancylite-(La), calcite, catapleiite, dolomite, ferrobustamite, fluorapatite, hemimorphite, pectolite, sphalerite, strontianite.
The name refers to the Taseq slope of the Ilímaussaq alkaline complex near which the first specimens were collected.