COLUMBITE  , a rare See also:

• MINERAL

mineral consisting of See also:

• IRON [symbol Fe, atomic weight 55.85 (0=16)]

iron niobate, FeNb206, in which the iron and niobium are replaced by varying amounts of See also:

• MANGANESE (symbol Mn; atomic weight, 54.93 (0=16)], a metallic chemical element. Its dioxide (pyrolusite)

manganese and See also:

• TANTALUM [symbol Ta, atomic weight 181•o (0=16)]

tantalum respectively, the See also:

• GENERAL
• GENERAL (Lat. generalis, of or relating to a genus, kind or class)

general See also:

• FORMULA
• FORMULA (Lat. diminutive of forma, shape, pattern, &c., especially used of rules of judicial procedure)

formula being (Fe, Mn) (Nb, Ta)206 . It was in this mineral that See also:

• CHARLES
• CHARLES (1270-1325)
• CHARLES (1421-1461)
• CHARLES (1525-1574)
• CHARLES (c. 1319-1364)
• CHARLES (Fr. Charles; Span. Carlos; Ital. Carlo; Ger. Karl; derived from O.H.G. Charal,latinized as Carolus, meaning originally " man ": cf. Mod.Ger., Kerl," fellow," A.S. ceorl, Mod. Eng. " churl ")
• CHARLES (KARL EITEL ZEPHYRIN LUDWIG; in Rum. CAROL)
• CHARLES [KARL ALEXANDER] (1712-1780)
• CHARLES, ELIZABETH (1828-1896)
• CHARLES, JACQUES ALEXANDRE CESAR (1746-1823)
• CHARLES, THOMAS (1755-1814)

Charles Iatchett discovered, in 18or, the See also:

• ELEMENT (Lat. elementum)

element niobium, which he himself called See also:

• COLUMBIUM, or NIOBIUM (symbol Cb or Nb, atomic weight 94)

columbium after the See also:

• COUNTRY (from the Mid. Eng. contre or contrie, and O. Fr. cuntree; Late Lat. contrata, showing the derivation from contra, opposite, over against, thus the tract of land which fronts the sight, cf. Ger. Gegend, neighbourhood)

country (See also:

• COLUMBIA

Columbia or See also:

• AMERICA

America) whence came the specimen in the See also:

• BRITISH

British Museum collection which he examined . The See also:

• SPECIES

species . has also been called niobite . It crystallizes in the orthorhombic See also:

• SYSTEM

system, and the See also:

• BLACK
• BLACK, ADAM (1784-1874)
• BLACK, JEREMIAH SULLIVAN (1810–1883)
• BLACK, WILLIAM (1841-1898)

black, opaque crystals are often very brilliant with a sub-metallic lustre . Twinned crystals are not uncommon, and there is a distinct cleavage parallel to the See also:

• FACE (from Lat. fades, derived either from facere, to make, or from a root fa-, meaning " appear "; cf. Gr. cbatvstv)

face marked See also:

• BIN

bin the figure . Hardness 6; specific gravity 5.3 . With increasing amount of tantalum the specific gravity increases up to 7.3, and members at this end of the See also:

• SERIES (a Latin word from serere, to join)

series are known as tantalite (FeTa2O6) . Specimens in which the iron is largely replaced by manganese are known as manganocolumbite or manganotantalite, according as they contain more niobium or more tantalum . Columbite occurs as crystals and compact masses in See also:

• GRANITE (adapted from the Ital. granite, grained; Lat. granum, grain)

granite and See also:

• PEGMATITE (from Gr. 1r3 y ea, a bond)

pegmatite at Rabenstein in See also:

• LOWER

Lower See also:

• BAVARIA (Ger. Bayern)

Bavaria, the Ilmen Mountains in the Urals, Haddam in See also:

• CONNECTICUT

Connecticut, and several other localities in the See also:

• UNITED

United States; also in the See also:

• CRYOLITE

cryolite of See also:

• GREENLAND (Danish, &c., Gronland)

Greenland . Tantalite is from See also:

• FINLAND (Finnish, Suomi or Suomenmaa)

Finland, and it has recently been found in some abundance in the deposits of cassiterite in the See also:

• TIN (Lat.- stannum, whence the chemical symbol " Sn "; atomic weight =117.6, 0=16)

tin-See also:

• FIELD (a word common to many West German languages, cf. Ger. Feld, Dutch veld, possibly cognate with O.E. f olde, the earth, and ultimately with root of the Gr. irAaror, broad)
• FIELD, CYRUS WEST (1819-1892)
• FIELD, DAVID DUDLEY (18o5-1894)
• FIELD, EUGENE (1850-1895)
• FIELD, FREDERICK (18o1—1885)
• FIELD, HENRY MARTYN (1822-1907)
• FIELD, JOHN (1782—1837)
• FIELD, MARSHALL (183 1906)
• FIELD, NATHAN (1587—1633)
• FIELD, STEPHEN JOHNSON (1816-1899)
• FIELD, WILLIAM VENTRIS FIELD, BARON (1813-1907)

field of Greenbushes in the See also:

• BLACKWOOD, WILLIAM (1776-1834)

Blackwood See also:

• DISTRICT

district, Western See also:

• AUSTRALIA

Australia . Dimorphous with columbite and tantalite are the tetragonal minerals tapiolite (= skogbolite) and mossite, so that the four See also:

• FORM (Lat. forma)

form an isodimorphous See also:

• GROUP

group with the general formula (Fe, Mn) (Nb, Ta)20s . Mossite is from a pegmatite vein near See also:

• MOSS

Moss in See also:

• NORWAY
• NORWAY (Norge)

Norway, and tapiolite is from Finland .

All these minerals contain tin in small amount . (L . J .