Tantalite-(Mg)

tantalite-(Mg)

tantalite-(Fe)

tantalite-(Mn)

columbite-(Fe)

Images

Formula: MgTa2O6
One of the tantalite minerals. Multiple oxide, columbite group, forms continuous solid-solution series with tantalite-(Fe) and with columbite-(Fe), tantalum-bearing mineral
Specific gravity: 6.7
Hardness: 5½
Streak: Brown-red
Colour: Black
Solubility: Insoluble in hydrochloric and nitric acid; slightly soluble in sulphuric acid
Environments:

Pegmatites

Tantalite-(Mg) occurs intergrown with tantalite-(Fe) and columbite-(Fe) as replacement rims on tantalite-(Mn) crystals in a granite pegmatite that cuts serpentinite near its contact with marble. Associated minerals include tantalite-(Fe), columbite-(Fe), microlite, calcite and sodic plagioclase (HOM).

Localities

At the type locality, the Lipovka mine, Lipovsk pegmatite field, Rezhevsky District, Sverdlovsk Oblast, Russia, intergrowths of tantalite-(Mg), tantalite-(Fe), columbite-(Fe) and uranium-bearing microlite form rims on tantalite-(Mn) crystals in albite variety andesine-calcite nests in a deeply desilicated granite pegmatite which crosscuts serpentinite near its contact with marble. Other associated minerals include dravite-uvite, chrysoberyl, phlogopite, magnesio-hornblende to edenite, cordierite, phenakite and clinochlore (Minrec 35.4.356-357).

Back to Minerals