Euxenite

Formula: (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)₂O₆

Mohs scale hardness: 5,5–6,5

Specific gravity: 4,7-5,0 g/cm³

Rare earth elements: Y, Sc, Dy, Eu, Tb, La, Ce

^{Rare earth content, %: (Y,Er)}2^O3 ^18.2–27.7;

^(Ce,La,...)2^O3 ^{16–30; REO}max^{= 40 %}

Other constituents, %: TiO2 16–30; Nb2O5

4.3–47.4; Ta2O5 1.3–23; ThO2 1–5; UO2 0.4–12

^{Mineralklasse: Oxide}

^{Uses: A minor ore of rare earth elements and uranium, sometimes cut as a gemstone and as mineral specimens.}

It contains calcium, niobium, tantalum, cerium, titanium, yttrium, and typically uranium and thorium, with soIt occurs in granite pegmatites 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; Minas Gerais, Brazil; Ampangabe, Madagascar; Ontario, Canada; and in Arizona, Wyoming and Colorado in the USA me other metals.

Area of application:Euxenite is used as an ore of the rare earth elements it contains. Rare large crystals have also been used in jewelry.

References

1. https://en.wikipedia.org

2. http://www.johnbetts-fineminerals.com/jhbnyc/mineralmuseum/picshow.php?id=56651

3. https://books.google.cl/books?id=jPskAQAAIAAJ&pg=RA4-PA13&lpg=RA4-PA13&dq=Green+Cove+Springs+Mine+monazite&source=bl&ots=8xH_PV9MoG&sig=MkXPfqzQ6OM4zmU2OWc-eHL2-GQ&hl=ru&sa=X&ved=0ahUKEwj6-bG1mfbMAhUDE5AKHYGfCWsQ6AEIKDAD#v=onepage&q&f=false