CARBONADO  , a name given in See also:

• BRAZIL
• BRAZIL, or BRASIL

Brazil to a dark massive See also:

• FORM (Lat. forma)

form of impure See also:

• DIAMOND

diamond, known also as " carbonate " and in See also:

• TRADE (O. Eng. trod, footstep, from tredan, to tread; in M. Eng. the forms teed, trod and trade appear, the last in the sense of a beaten track)
• TRADE, BOARD OF

trade simply as See also:

• CARBON (symbol C, atomic weight 12)

carbon . It is sometimes called See also:

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

black diamond . Generally it is found in small masses of irregular polyhedral form, black, See also:

• BROWN
• BROWN, CHARLES BROCKDEN (1771-181o)
• BROWN, FORD MADOX (1821-1893)
• BROWN, FRANCIS (1849- )
• BROWN, GEORGE (1818-188o)
• BROWN, HENRY KIRKE (1814-1886)
• BROWN, JACOB (1775–1828)
• BROWN, JOHN (1715–1766)
• BROWN, JOHN (1722-1787)
• BROWN, JOHN (1735–1788)
• BROWN, JOHN (1784–1858)
• BROWN, JOHN (1800-1859)
• BROWN, JOHN (1810—1882)
• BROWN, JOHN GEORGE (1831— )
• BROWN, ROBERT (1773-1858)
• BROWN, SAMUEL MORISON (1817—1856)
• BROWN, SIR GEORGE (1790-1865)
• BROWN, SIR JOHN (1816-1896)
• BROWN, SIR WILLIAM, BART
• BROWN, THOMAS (1663-1704)
• BROWN, THOMAS (1778-1820)
• BROWN, THOMAS EDWARD (1830-1897)
• BROWN, WILLIAM LAURENCE (1755–1830)

brown or dark-See also:

• GREY, CHARLES GREY, 2ND EARL (1764-1845)
• GREY, HENRY GREY, 3RD EARL (1802-1894)
• GREY, LADY JANE (1537-1554)
• GREY, SIR EDWARD
• GREY, SIR GEORGE (1812–1898)

grey in See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour, with a dull resinoid lustre; and breaking with a granular fracture, paler in colour,and in some cases much resembling that of See also:

• FINE

fine-grained See also:

• STEEL, FLORA ANNIE (1847– )

steel . Being slightly cellular, its specific gravity is rather less than that of crystallized diamond . It is found almost exclusively in the See also:

• STATE
• STATE, GREAT OFFICERS OF

state of See also:

• BAHIA

Bahia in Brazil, where it occurs in the cascalho or diamond-bearing See also:

• GRAVEL, or PEBBLE BEDS

gravel . See also:

• BORNEO

Borneo also yields it in small quantity . Formerly of little or no value, it came into use on the introduction of Leschot's diamond-drills, and is now extremely valuable for mounting in the steel crowns used for diamond-See also:

• BORING

boring . Having no cleavage, the carbon is less liable to fracture on the rotation of the See also:

• DRILL

drill than is crystallized diamond . The largest piece of carbonado ever recorded was found in Bahia in 1895, and weighed 3150 carats . Pieces of large See also:

• SIZE

size are, however, relatively less valuable than those of moderate dimensions, since they require the See also:

• EXPENDITURE

expenditure of much labour in reducing them to fragments of a suitable size for mounting in the drill-heads . See also:

• ILMENITE

Ilmenite has sometimes been mistaken in the See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South See also:

• AFRICAN

African mines for carbonado . (F .

W .