Mineral: Bismutotantalite zoned with Bismuth & Stibiotantalite (variety Nb-bearing) and with Albite and Tourmaline (Group)
Locality: Ifẹ, Osun State, Nigeria
Dimensions: 7 x 6 x 16 cm

Description: Ile-Ife Pegmatite District, Osun State, Nigeria Mass: 2988 g MIM number:2201 Large, wery well-formed crystal exhibiting unusual morphology for orthorhombic Na-Tb oxides, with elongated, tapered terminal faces. It displays a visually striking color zonation, from translucent, smoke-gray and brown cores (bismuth and niobium-rich stibiotantalite), to opaque black rims (bismutotantalite). There is minor matrix on one corner which is composed of albite and green tourmaline (the main mineral from this pegmatite). Photographer: AINU / Augustin de Valence

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