Babefphite is a rare phosphate mineral with the general formula BaBe(PO₄)(F,OH). The name is given for its composition (Ba meaning barium

Barium

Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...

, Be meaning beryllium

Beryllium

Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...

, F meaning fluorine

Fluorine

Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...

, and P for phosphorus

Phosphorus

Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...

).

Crystallography

Babefphite is tetragonal, which means crystallographically, it contains two horizontal and interchangeable equal axes (a_{1 and 2}) and a longitudinal axis (c). It belongs to the 4/m 2/m 2/m point group; meaning it has four horizontal axes of twofold symmetry

Symmetry

Symmetry generally conveys two primary meanings. The first is an imprecise sense of harmonious or aesthetically pleasing proportionality and balance; such that it reflects beauty or perfection...

, two of which coincide with the crystallographic axes (a₁) and (a₂) and the remaining two at 45° to the (a₁) and (a₂).

Optical properties

Babefphite is an anisotropic mineral meaning that the velocity of light passing though it will vary depending on the direction of travel. When measured against Canada Balsam

Canada balsam

Canada balsam, also called Canada turpentine or balsam of fir, is a turpentine which is made from the resin of the balsam fir tree of boreal North America...

 it will display moderate positive relief. Relief is an optical property that relates the index of refraction of a mineral versus the index of refraction of another material. Positive relief denotes light being bent toward the mineral. Negative relief means the light is bent toward the mounting material. In the case of optical mineralogy, this other material is most often whatever material is used to mount the mineral in question in thin section. Based on the white color of babefphite in hand sample it is likely that it appears clear in thin section under plane polarized light. Due to its anisotropic nature, it has the possibility of displaying very weak pleochroism under the same conditions. Pleochroism

Pleochroism

Pleochroism is an optical phenomenon in which a substance appears to be different colors when observed at different angles with polarized light.- Background :Anisotropic crystals will have optical properties that vary with the direction of light...

 is defined as a change of color, on rotation, of plane light. It occurs when the extraordinary and ordinary rays of light are absorbed differently, thereby diplaying different colors. The wider the difference in the rays the more dramatic the color change. Babefphite is also weakly birefringent. Birefringence

Birefringence

Birefringence, or double refraction, is the decomposition of a ray of light into two rays when it passes through certain anisotropic materials, such as crystals of calcite or boron nitride. The effect was first described by the Danish scientist Rasmus Bartholin in 1669, who saw it in calcite...

 is an optical property that is determined by the direction that light passes through a mineral.

Occurrence

Babefphite was first described in 1966 for an occurrence at the Aunik fluorite-rare metals deposit, Buryatia

Buryatia

The Republic of Buryatia is a federal subject of Russia . Its capital is the city of Ulan-Ude. Its area is with a population of 972,658 .-Geography:...

, Eastern-Siberian Region, Russia. It has also been reported from the Rožná pegmatite in the Vysočina Region, Moravia

Moravia

Moravia is a historical region in Central Europe in the east of the Czech Republic, and one of the former Czech lands, together with Bohemia and Silesia. It takes its name from the Morava River which rises in the northwest of the region...

, Czech Republic

Czech Republic

The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....

.

In the Siberian occurrence it occurs in residual material above rare earth

Rare earth element

As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...

 metal bearing skarn

Skarn

Skarn is an old Swedish mining term originally used to describe a type of silicate gangue, or waste rock, associated with iron-ore bearing sulfide deposits apparently replacing Archean age limestones in Sweden's Persberg mining district. In modern usage the term "skarn" has been expanded to refer...

s associated with alkaline intrusive bodies. It occurs with zircon

Zircon

Zircon is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO4. A common empirical formula showing some of the range of substitution in zircon is 1–x4x–y...

, ilmenorutile, fluorite

Fluorite

Fluorite is a halide mineral composed of calcium fluoride, CaF2. It is an isometric mineral with a cubic habit, though octahedral and more complex isometric forms are not uncommon...

, phenakite

Phenakite

Phenakite or phenacite is a fairly rare nesosilicate mineral consisting of beryllium orthosilicate, Be2SiO4. Occasionally used as a gemstone, phenakite occurs as isolated crystals, which are rhombohedral with parallel-faced hemihedrism, and are either lenticular or prismatic in habit: the...

, scheelite

Scheelite

Scheelite is a calcium tungstate mineral with the chemical formula CaWO4. It is an important ore of tungsten. Well-formed crystals are sought by collectors and are occasionally fashioned into gemstones when suitably free of flaws...

, bertrandite

Bertrandite

Bertrandite is a beryllium sorosilicate hydroxide mineral with composition: Be4Si2O72. Bertrandite is a colorless to pale yellow orthorhombic mineral with a hardness of 6-7. It is commonly found in beryllium rich pegmatites and is in part an alteration of beryl. Bertrandite often occurs as a...

, albite

Albite

Albite is a plagioclase feldspar mineral. It is the sodium endmember of the plagioclase solid solution series. As such it represents a plagioclase with less than 10% anorthite content. The pure albite endmember has the formula NaAlSi3O8. It is a tectosilicate. Its color is usually pure white, hence...

, microcline

Microcline

Microcline is an important igneous rock-forming tectosilicate mineral. It is a potassium-rich alkali feldspar. Microcline typically contains minor amounts of sodium. It is common in granite and pegmatites. Microcline forms during slow cooling of orthoclase; it is more stable at lower temperatures...

 and quartz

Quartz

Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

.