Images
Formula: MgNb4O11.8-12H2O
Hydrated oxide, franconite group,
niobium-bearing mineral
Crystal System: Monoclinic
Specific gravity: 2.95 measured, 2.99 calculated
Hardness: 3
Streak: White
Colour: White
Solubility: Insoluble in dilute hydrochloric acid
Environments
Carbonatites
Hydrothermal environments
Localities
At the type locality, the Vuoriyarvi alkaline-ultrabasic massif, Northern Karelia, Murmansk Oblast, Russia,
ternovite occurs as white spherulites, to 0.5 mm in diameter, consisting of radiating blades averaging
0.1 x 0.003 x 0.005 mm3. Ternovite, franconite, and
hochelagaite occur as latestage hydrothermal minerals in dissolution
voids that formed as a result of dolomitisation of pyrochlore-bearing
calcite
carbonatites. Associated late-stage minerals are
dolomite, magnesite,
serpentine, baryte,
pyrite, ancylite-(Ce) and
belkovite
(AM 83.185-189).
Back to Minerals