Euxenite, or euxenite-(Y) (the official mineralogical name), is a brownish black
mineral with a metallic
luster.
Chemistry
It contains
calcium,
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 ...
,
tantalum,
cerium,
titanium,
yttrium, and typically
uranium and
thorium, with some other
metals. The chemical formula is . It is commonly partially
amorphous
In condensed matter physics and materials science, an amorphous solid (or non-crystalline solid, glassy solid) is a solid that lacks the long-range order that is characteristic of a crystal.
Etymology
The term comes from the Greek ''a'' ("wi ...
due to
radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes:
* ''electromagnetic radiation'', such as radio waves, microwaves, infrared, visi ...
damage.
Euxenite forms a continuous series with the titanium rich
polycrase-(Y)
Polycrase or polycrase-(Y) is a black or brown metallic complex uranium yttrium oxide mineral with the chemical formula . It is amorphous. It has a Mohs hardness of 5 to 6 and a specific gravity of 5. It is radioactive due to its uranium content ( ...
having the formula .
Name and discovery
It was first described in 1870 and named for from the Greek (εὔξενος), ''hospitable'' or ''friendly to strangers'', in allusion to the many rare elements that it contains.
[
]
Occurrence
It occurs in granite pegmatite
A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than and sometimes greater than . Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic com ...
s and detrital black sands.[
It is found in many locations worldwide, notably its type locality in Jølster, Sunnfjord, Norway.][ Other locations include the Ural Mountains of Russia; ]Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...
; Minas Gerais, Brazil; Ampangabe, Madagascar; Ontario, Canada; and in Arizona, Wyoming and Colorado in the US.[http://www.galleries.com/minerals/oxides/euxenite/euxenite.htm Mineral Galleries]
Use
Euxenite is used as an ore of the rare earth elements it contains. Rare large crystals have also been used in jewelry.[
]
References
{{Titanium minerals
Calcium minerals
Thorium minerals
Uranium minerals
Lanthanide minerals
Niobium minerals
Tantalum minerals
Titanium minerals
Yttrium minerals
Cerium minerals
Oxide minerals
Orthorhombic minerals
Minerals in space group 62
Minerals described in 1870
