AM_Bismutocolumbite Formula: Bi (Nb.79 Ta.21) O4 Name: Bismutocolumbite Unit cell: 5.668 11.725 4.971 90.0 90.0 90.0 , V=330.36 Space group: PNNA (52)

Zubkova N V , Pushcharovsky D Y , Giester G , Smolin A S , Tillmanns E , Brandstatter F , Hammer V , Peretyazhko I S , Sapozhnikov A N , Kashaev A A , Neues Jahrbuch fur Mineralogie, Monatshefte , 2002 (2002) p.145-159, Bismutocolumbite, Bi(Nb.79Ta.21)O4, stibiocolumbite, Sb(Nb.67Ta.33)O4 and their, structural relation to the other ABO4 minerals with, stibiotantalite (SbTaO4) structure, Locality: Malkhan field, Central Transbaikalia, Russia