Brown black tanteuxenite associated to tantalite from DR Congo (Liha, Sankuru, DR Congo). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Tanteuxenite-(Y)
Tanteuxenite-(Y) is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula Y(Ta,Nb,Ti)₂(O,OH)₆.
It is a member of the Columbite structural group.
Key properties: Mohs hardness 5.5–6; specific gravity 5.77–5.87; Resinous luster.
IMA symbol Ttx-Y, IMA status: approved, named in 1928.
A detrital mineral in tin placers (Western Australia); in a granite pegmatite (Craveggia, Italy).
It is found associated with Striiverite, columbite, ilmenite, tourmaline, spessartine, beryl, allanite, monazite, xenotime (Craveggia, Italy).
The name refers to its relation to euxenite, with TANTalum greater than niobium.