Tantalite

{{Short description|Tantalum ore}}

{{confused|Tantalit|Tantalate}}

{{Infobox mineral

| name = Tantalite

| boxwidth =

| boxbgcolor =

| image = Tantalite.jpg

| imagesize = 260px

| alt =

| caption = Tantalite, Pilbara district, Australia

| category = Oxide minerals

| formula = (Fe,Mn)Ta₂O₆

| IMAsymbol = Ttl{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}

| molweight =

| strunz = 4.DB.35

| dana =

| system = Orthorhombic

| class = Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)

| symmetry = Pbcn (no. 60)

| unit cell =

| color = Dark black, iron-black to dark brown, reddish brown

| colour =

| habit =

| twinning =

| cleavage = Good in one direction

| fracture = Subconchoidal

| tenacity =

| mohs = 6–6.5

| luster = Submetallic to almost resinous

| streak = Brownish-red to black

| diaphaneity =

| gravity = 8.0+

| density =

| polish =

| opticalprop =

| refractive =

| birefringence =

| pleochroism =

| 2V =

| dispersion =

| extinction =

| length fast/slow =

| fluorescence =

| absorption =

| melt =

| fusibility =

| diagnostic =

| solubility =

| impurities =

| alteration =

| other =

| prop1 =

| prop1text =

| references = {{cite web|title=TANTALITE (Iron Manganese Tantalum Niobium Oxide)|url=http://www.galleries.com/Tantalite|publisher=Galleries.com|access-date=2011-10-25}}[http://www.mindat.org/min-3882.html Tantalite]. Mindat.org (2011-09-07). Retrieved on 2011-10-30.

}}

The mineral group tantalite [(Fe, Mn)Ta₂O₆] is the primary source of the chemical element tantalum, a corrosion (heat and acid) resistant metal. It is chemically similar to columbite, and the two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides. However, tantalite has a much greater specific gravity than columbite (8.0+ compared to columbite's 5.2). Iron-rich tantalite is the mineral tantalite-(Fe) or ferrotantalite and manganese-rich is tantalite-(Mn) or manganotantalite.

Tantalite is also very close to tapiolite. Those minerals have the same chemical composition, but different crystal symmetry: orthorhombic for tantalite and tetragonal for tapiolite.{{cite journal|author=P. Cerny|title=The tantalite-tapiolite gap: natural assemblages versus experimental data|journal= Canadian Mineralogist |volume=30 |year=1992|pages= 587|url=http://rruff.geo.arizona.edu/doclib/cm/vol30/CM30_587.pdf |display-authors=etal}}

Tantalite is black to brown in both color and streak. Manganese-rich tantalites can be brown and translucent.