Formula: Mn2+TiTa2O8
Oxide, wodginite group, columbite supergroup, manganese-, titanium- and tantalum- bearing mineral
Crystal System: Monoclinic
Specific gravity: 6.86 measured, 6.89 calculated
Hardness: 5½
Streak: Dark brown
Colour: Dark brown to black
Luminescence: Not fluorescent under UV
Common impurities: Fe,Sn,Sc,Nb



At the type locality, the Tanco Mine, Bernic Lake, Lac-du-Bonnet area, Manitoba, Canada, titanium is largely a ubiquitous component in wodginite group minerals; however, titanium contents are typically low. The first titanium-rich variety of wodginite encountered was the type ferrowodginite sample; subsequently a re-examination of the tantalum- and niobium- oxide minerals at Tanco led to the discovery of titanowodginite, with TiO2 contents as high as 10.4wt %. Type titanowodginite occurs in a sample of tantalum ore from the workings of the Tanco pegmatite. The mineral occurs with microlite and columbite-(Mn) as disseminations in a silicate matrix consisting of saccharoidal albite plus quartz with minor muscovite and beryl. Type titanowodginite occurs as euhedral, bipyramidal crystals ranging from a few mm to 1 cm long. It occurs most often in irregular clusters of crystals, but it also occurs as individual crystals. (CM 30.633-638).

At the Separation Rapids Lithium Project (Separation Lake area), Kenora District, Ontario, Canada, wodginite, ferrowodginite and titanowodginite have been discovered in rare-element granitic pegmatites which occur in the Separation Rapids pegmatite field. The pegmatites intrude a metavolcanic (greenstone) belt, where they are associated with a rare-element-enriched granitic intrusion, the Separation Rapids pluton.
At Separation Rapids, the rare-metal oxides follow two distinct evolutionary paths:
(i) columbite-(Fe)columbite-(Fe) + ferrowodginitetantalite-(Fe) + ferrowodginitemicrolite group minerals
(ii) columbite-(Mn)columbite-(Mn) + wodginitetantalite-(Mn) + wodginitemicrolite group minerals (CM 36.2.637–658).

At Fonte del Prete, San Piero in Campo, Campo nell'Elba, Livorno Province, Tuscany, Italy, the rare-element-enriched granitic pegmatite dike displays LCT(lithium - cesium - tantalum)-type geochemical features. The dike is characterised by complex asymmetrical zoning, with miarolitic pockets containing primitive or highly evolved assemblages. There is a noteworthy presence of niobium and tantalum oxides and complex oxides, occurring mainly in the pockets. Euxenite-(Y), polycrase-(Y), uranium- and bismuth- rich polycrase-(Y), and columbite-(Fe) occur in the primitive pockets in the central part (core zone), whereas uranium- and bismuth- rich polycrase-(Y), uranopolycrase, columbite-(Mn), tantalite-(Mn), wolframoixiolite, titanowodginite and microlite are found in the evolved pockets, at the extremities of the dike. Niobium-bearing rutile and euxenite-(Y) are also found in the massive pegmatite.
During the evolution of the pegmatite, a volatile-rich melt with a high content of rare elements reached saturation in aqueous vapour. Minerals of titanium, niobium, iron, yttrium + heavy rare-earth elements occur in the primitive pockets; the enrichment of manganese, tantalum and tungsten in the evolved ones led to the crystallisation of minerals with high Ta/(Ta + Nb) and Mn/(Mn + Fe) values, such as tantalite-(Mn), microlite and titanowodginite. The polycrase-(Y) is unusually enriched in bismuth and uranium, and is zoned from a bismuth-poor core to a bismuth-rich rim. (CM 40.3.799–814).

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