Wiktionary
bukovite
n. (context mineral English) A tetragonal-ditetragonal dipyramidal mineral containing copper, iron, selenium, and thallium.
Wikipedia
Bukovite
Bukovite is a rare selenide mineral with formula TlCuFeSe. It is a brown to black metallic mineral which crystallizes in the tetragonal system.
It was first described in 1971 for an occurrence in the Bukov uranium mine, Rožná deposit, Vysočina Region, Moravia, Czech Republic. It has also been reported in Skrikerum, near Tryserum, Kalmar, Sweden; near Vernet-la-Varenne, Puy-de-Dôme, France; and Tuminico, Sierra de Cacho, La Rioja Province, Argentina.