Aleksandrovite
Aleksandrovite is an IMA-recognized mineral species in the silicate class, with the chemical formula KCa₇Sn₂Li₃Si₁₂O₃₆F₂.
It crystallizes in the monoclinic crystal system (space group C2/c). It is a member of the Baratovite structural group.
Key properties: Mohs hardness 4–4.5; specific gravity 3.05; White streak; Vitreous, pearly on cleavage surfaces luster; optically biaxial.
IMA symbol Asd, IMA status: approved, named in 2009.
Found in a zoned microcline-calcite vein with aegirine-hedenbergite, quartz, and albite in a glacial moraine boulder. The region contains carbonatites and an alkaline massif.
It is found associated with Miserite, baratovite, katayamalite, Zr and hydroxyl analogues of alexandrovite, fluorite, Sn-titanite, bazirite, pabstite, Sn-sogdianite, sugilite.
The mineral was named to honor the Russian geochemist, geologist, and mineralogist Stanislav Mikhailovich Aleksandrov (b. 1932) for his contributions to the geology, geochemistry.