Wodginite

Wodginite is a manganese, tin, tantalum oxide mineral with formula Mn²⁺(Sn,Ta)Ta₂O₈. It may include significant niobium.[1][2]

Wodginite
Wodginite over cassiterite
General
Category	Oxide - Tantalate mineral
Formula (repeating unit)	Mn^2+(Sn,Ta)Ta2O8
Strunz classification	4.DB.40
Dana classification	08.01.08.01
Crystal system	Monoclinic
Crystal class	Prismatic (2/m) (same H-M symbol)
Identification
Color	Reddish brown, dark brown to black
Crystal habit	Flattened dipyramidal to prismatic crystals in radiating groups; granular, massive.
Twinning	Very common as penetration twins
Cleavage	none
Fracture	Irregular
Tenacity	Brittle
Mohs scale hardness	5.5
Luster	Sub-metallic
Streak	Brown
Diaphaneity	Opaque, translucent in thin fragments
Specific gravity	7.19–7.36
References	[1][2][3]

Background

Wodginite was first described in 1963 for an occurrence in the Wodgina pegmatite, Wodgina, Pilbara Region, Western Australia.[3]

Typical occurrence of Wodginite occurs in zoned pegmatites in amphibolite. It is associated with tantalite, albite, quartz, muscovite, tapiolite, microlite and microcline.[1]

It occurs in pegmatites in a wide variety of locations. The most studied is the Tanco pegmatite in Manitoba, Canada; also in Red Lake, Ontario. It is reported from the Strickland quarry, Portland, Middlesex County, Connecticut; the Herbb #2 pegmatite, Powhatan County, Virginia; the McAllister mine, Rockford, Coosa County, Alabama; the Peerless mine, Pennington County, South Dakota. Also from Paraíba and Minas Gerais, Brazil; Krasonice, Czech Republic; Orivesi, Finland; Kalba, eastern Kazakhstan; Ankole, Uganda; Miami district, Zimbabwe and Karibib and Kohero, Namibia.[1][3]

The figure shows, that the columbite group (including tantalite) and wodginite can be seen as a superstructure of ixiolite.[4]

References

1. Handbook of Mineralogy
2. Webmineral data
3. Mindat.org
4. Ercit, T. S.; Hawthorne, F.; Cerny, P. (1992). "The wodginite group: I. structural crystallography". Canadian Mineralogist. 30: 597–611.

• Nickel, E H; Rowland, J F; McAdam, R C (1963). "Wodginite - A new tin-manganese tantalate from Wodgina, Australia and Bernic lake, Manitoba" (PDF). The Canadian Mineralogist. 7: 390–402.