euxenite
noun
eux·e·nite
ˈyüksəˌnīt
plural -s
: a brownish black mineral (Y, Ca, Ce, U, Th) (Cb, Ta, Ti)2O6 that consists of oxide of calcium, cerium, columbium, tantalum, titanium, and uranium, that has a metallic luster, and that is isomorphous with polycrase (hardness 6.5, specific gravity 4.7–5.0)
Word History
Etymology
German euxenit, from Greek euxenos hospitable (from eu- + xenos guest, stranger) + German -it -ite; from the rare elements it contains