Single crystal group of the rare zirconium mineral sogdianite from the type locality: Dara-i-Pioz Glacier, Tien Shan Mountains, Region of Republican Subordination, Tajikistan. — Photo: David Hospital · CC BY-SA 4.0
Sogdianite
Sogdianite is an IMA-recognized mineral species in the silicate class, with the chemical formula KZr₂Li₃Si₁₂O₃₀.
It crystallizes in the hexagonal crystal system (space group P6/mcc). It is a member of the Milarite structural group.
Key properties: Mohs hardness 5–7; specific gravity 2.76–2.9; Vitreous luster; optically uniaxial.
IMA symbol Sog, IMA status: approved, named in 1968.
Found in a pegmatite vein with a composition about that of an alkalic granite.
It is found associated with Thorite, stillwellite, pyrochlore, tienshanite, thorite, cesium kupletskite, microcline, quartz, aegirine (Dara-i-Pioz massif, Tajikistan); aegirine.
The name refers to Sogdiana, an ancient Central Asian state.