vlasovite

{{Infobox mineral | name = Vlasovite | category = Silicate mineral | boxwidth = 24 | boxbgcolor = | image = Vlasovite-Gittinsite-Eudialyte-213097.jpg | imagesize = 260px | caption = Golden-amber vlasovite crystal frozen in cherry-red eudialyte matrix | formula = Na2ZrSi4O11 | IMAsymbol = Vsv | molweight = 425.54 g/mol | strunz = 9.DM.25 (10 ed) 8/F.34-20 (8 ed) | dana = 66.2.2.1 | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = B2/b | color = Usually colorless or brownish | habit = Crystals rare; usually grains and aggregates | twinning = Uncommon, with twin plane {010} | cleavage = Distinct on {010} | fracture = Irregular to conchoidal | tenacity = Brittle | mohs = 6 | luster = Greasy; vitreous to pearly on cleavage | refractive = Nx = 1.607, Ny = 1.623, Nz = 1.628 | opticalprop = Biaxial (−) | birefringence = | pleochroism = (x): colorless. (y): colorless. (z): colorless. | streak = White | gravity = 2.97 | melt = | fusibility = | diagnostic = | solubility = Nearly insoluble in HCl and HNO3, but dissolves easily in a mixture of HF and H2SO4 | diaphaneity = Transparent to translucent | other = Non-fluorescent, but altered material fluoresces yellow-orange | references = }}

Vlasovite is a rare inosilicate (chain silicate) mineral with sodium and zirconium, with the chemical formula Na2ZrSi4O11. It was discovered in 1961 at Vavnbed Mountain in the Lovozero Massif, in the Northern Region of Russia. The researchers who first identified it, R P Tikhonenkova and M E Kazakova, named it for Kuzma Aleksevich Vlasov (1905–1964), a Russian mineralogist and geochemist who studied the Lovozero massif, and who was the founder of the Institute of Mineralogy, Geochemistry, and Crystal Chemistry of Rare Elements, Moscow, Russia.