Faizievite is a very rare mineral with the formula K₂Na(Ca₆Na)Ti₄Li₆Si₂₄O₆₆F₂.Agakhanov, A.A., Pautov, L.A., Uvarova, Y.A., Sokolova, E.V., Hawthorne, F.C., Karpenko, V.Y., and Gafurov, F.G., 2007. Faizievite, K₂Na(Ca₆Na)Ti₄Li₆Si₂₄O₆₆F₂ - a new mineral species. New data on minerals 42, 5-10 This triclinic mineral is chemically related to baratovite and katayamalite. Faizievite is a single-locality mineral, coming from the moraine of the Darai-Pioz glacier,

Tien Shan The Tian Shan,, , otk, 𐰴𐰣 𐱅𐰭𐰼𐰃, , tr, Tanrı Dağı, mn, Тэнгэр уул, , ug, تەڭرىتاغ, , , kk, Тәңіртауы / Алатау, , , ky, Теңир-Тоо / Ала-Тоо, , , uz, Tyan-Shan / Tangritog‘ ...

Mountains, Tajikistan. Alkaline rocks of this site are famous for containing numerous rare minerals, often enriched in boron, caesium, lithium, titanium, rare earth elements, barium, and others.

Occurrence and association

Faizievite was detected in quartz boulders, together with

aegirine Aegirine is a member of the clino pyroxene group of inosilicate minerals. Aegirine is the sodium endmember of the aegirine- augite series. Aegirine has the chemical formula Na Fe Si2 O6 in which the iron is present as Fe3+. In the aegirine-augit ...

, baratovite,

fluorite Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2. It belongs to the halide minerals. It crystallizes in isometric cubic habit, although octahedral and more complex isometric forms are not uncommon. The Mohs sca ...

, leucosphenite,

pectolite Pectolite is a white to gray mineral, sodium, Nacalcium, Ca2silicon, Si3oxygen, O8(Ohydrogen, H), sodium calcium hydroxide inosilicate. It crystallizes in the triclinic system typically occurring in radiated or fibrous crystalline masses. It has a ...

, and

polylithionite Lepidolite is a lilac-gray or rose-colored member of the mica group of minerals with chemical formula . It is the most abundant lithium-bearing mineral and is a secondary source of this metal. It is the major source of the alkali metal rubidium. ...

Notes on chemistry and structure

Strontium Strontium is the chemical element with the symbol Sr and atomic number 38. An alkaline earth metal, strontium is a soft silver-white yellowish metallic element that is highly chemically reactive. The metal forms a dark oxide layer when it is ex ...

and trace amounts of

rubidium Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher ...

barium Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Th ...

and

niobium Niobium is a chemical element with chemical symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has sim ...

are present in the structure of faizievite. One of the sodium sites is partially vacant, and fluorine may be substituted by oxygen.

Relation to other minerals

Faizievite is related to

beryl Beryl ( ) is a mineral composed of beryllium aluminium silicate with the chemical formula Be3Al2Si6O18. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring, hexagonal crystals of beryl can be up to several mete ...

and

osumilite Osumilite is a very rare potassium-sodium-iron-magnesium-aluminium silicate mineral. Osumilite is part of the milarite group (also known as the milarite-osumilite group) of cyclosilicates. Characteristics Osumilite chemical formula is .Don S. G ...

groups of minerals.

References

Silicate minerals Cyclosilicates Lithium minerals Titanium minerals Potassium minerals Sodium minerals Calcium minerals Fluorine minerals Triclinic minerals Minerals in space group 2 {{mineral-stub