Tantite is a rare tantalum oxide mineral with formula: Ta2O5.
Tantite forms transparent microscopic colorless triclinic - pedial crystals with an adamantine luster.
Chemical analyses show minor inclusion (1.3%) of niobium oxide.
It has also been reported from a pegmatite complex in Florence County, Wisconsin.
Associated mineral species include elbaite, lepidolite, spodumene, columbite-tantalite, wodginite, and microlite.