TOPAZ  , a See also:

• MINERAL

mineral usually found in connexion with granitic rocks and used, when See also:

• FINE

fine, as a See also:

• GEM (Lat. gemma, a bud,—from the root gen, meaning " to produce,"—or precious stone; in the latter sense the Greek term is > d>os)
• GEM, ARTIFICIAL

gem-See also:

• STONE
• STONE (0. Eng. shin; the word is common to Teutonic languages, cf. Ger. Stein, Du. steen, Dan. and Swed. sten; the root is also seen in Gr. aria, pebble)
• STONE, CHARLES POMEROY (1824-1887)
• STONE, EDWARD JAMES (1831-1897)
• STONE, FRANK (1800-1859)
• STONE, GEORGE (1708—1764)
• STONE, LUCY [BLACKWELL] (1818-1893)
• STONE, MARCUS (184o— )
• STONE, NICHOLAS (1586-1647)

stone . It is believed that the topaz of See also:

• MODERN

modern mineralogists was unknown to the ancients, and that the stone described under the name of ro1r6. ios, in allusion to its occurrence on an See also:

• ISLAND (O.E. ieg =isle, +land')

island in the Red See also:

• SEA (in O. Eng. sae, a common Teutonic word; cf. Ger. See, Dutch Zee, &c.; the ultimate source is uncertain)
• SEA, COMMAND OF THE

Sea known as roirb . .os vi)o-os, was the mineral which is now termed See also:

• CHRYSOLITE

chrysolite or See also:

• PERIDOT

peridot (q.v.) . The See also:

• HEBREW

Hebrew pitdah, translated " topaz " in the Old Testament, may also have been the chrysolite . Topaz crystallizes in the orthorhombic See also:

• SYSTEM

system, usually with a prismatic See also:

• HABIT (through the French from Lat. habitus, from habere, to have, hold, or, in a reflective sense, to be in a certain condition; in many of the English senses the French use habitude, not habit)

habit (See also:

• FIGS

figs . 1 and 2) . Many of the crystals, like those from See also:

• SAXONY
• SAXONY (Ger. Provinz Sachsen)

Saxony and See also:

• SIBERIA

Siberia, are See also:

• RICH, BARNABE (c. 1540-1617)
• RICH, CLAUDIUS JAMES (1787-1821)
• RICH, JOHN (1692-1761)
• RICH, PENELOPE, LADY (c. 1562–1607)
• RICH, RICHARD, 1ST BARON RICH (1490?-1567)

rich in faces, and See also:

• PRESENT

present with the prisms a complicated See also:

• COMBINATION (Lat. combinare, to combine)

combination of pyramids and domes . The faces of the See also:

• PRISM (Gr. rrpivµa, properly a thing sawn, Irpii"ety, to saw)

prism-See also:

• ZONE (Gr. 'WV77, a girdle, from 'wvvLvay to gird)

zone are usually striated vertically . Doubly-terminated crystals are rare, and sometimes apparently See also:

• HEMIMORPHIC

hemimorphic . The mineral presents a perfect cleavage transverse to the See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

long See also:

• AXIS (Lat. for " axle ")

axis of the prism, and the cleavage-See also:

• PLANE

plane often has a pearly lustre . The chemical See also:

• COMPOSITION
• COMPOSITION (Lat. compositio, from componere, to put together)

composition of the topaz has given rise to much discussion, but it is now generally regarded as an See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium fluo-silicate having the See also:

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

formula Al2F2SiO4 . It was shown by See also:

• PROFESSOR (the Latin noun formed from the verb profiteri, to declare publicly, to acknowledge, profess)

Professor S .

L . Penfield and Mr J . C . See also:

• MINOR
• MINOR (Lat. for smaller, lesser)
• MINOR, ROBERT CRANNELL (1839-1904)

Minor that the See also:

• FLUORINE (symbol F, atomic weight 19)

fluorine may be partially replaced by hydroxyl . When strongly heated topaz suffers considerable loss of See also:

• WEIGHT

weight . See also:

• SIR

Sir D . See also:

• BREWSTER, SIR DAVID (1781–1868)
• BREWSTER, WILLIAM (c. 1566–1644)

Brewster found in topaz numerous microscopic cavities containing fluids, some of which have received the names of brewsterlinite and cryptolinite . Possibly some of the liquid inclusions may be See also:

• HYDROCARBONS

hydrocarbons . The topaz, when pure, may be colourless, and if cut as a brilliant has been mistaken for See also:

• DIAMOND

diamond . It has, too, the same specific gravity, about 3.5 . It is, however, greatly inferior in hardness, the hardness of topaz being only 8; and it has See also:

• LOWER

lower refractivity and dispersive See also:

• POWERS, HIRAM (1805-1873)

powers: moreover, being an orthorhombic mineral, it possesses See also:

• DOUBLE
• DOUBLE (from the Mid. Eng. duble, the form which gives the present pronunciation, through the Old Er. duble, from Lat. duplus, twice as much)

double See also:

• REFRACTION
• REFRACTION (Lat. refringere, to break open or apart)

refraction . From See also:

• PHENACITE

phenacite and from See also:

• ROCK
• ROCK (O.Fr. rake, Sp. rota, Ital. rocca; possibly from a Lat. form rupica, from rupes, rock)
• ROCK, DANIEL (1799–187t)

rock-crystal, for which it may be mistaken, it is distinguished by being biaxial and by having a much higher specific gravity .

The topaz becomes electric by See also:

• HEATING

heating, by See also:

• FRICTION (from Lat. fricare, to rub)

friction or by pressure . Colourless limpid topazes are known in See also:

• BRAZIL
• BRAZIL, or BRASIL

Brazil as pingos d'agoa, or " drops of See also:

• WATER

water," whilst in See also:

• ENGLAND
• ENGLAND, THE CHURCH OF

England they pass 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 as " See also:

• MINAS [MINOIDES] (c. 1790-186o)

minas novas," from a locality in the See also:

• STATE
• STATE, GREAT OFFICERS OF

state of Minas Geraes in Brazil . Coloured topazes usually present various shades of yellow, See also:

• BLUE (common in different forms to most European languages)

blue or 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 . The pleochroism is fairly marked, the See also:

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

colour of the See also:

• SHERRY

sherry-yellow crystals from Brazil being generally resolved by thedichroscope into a brownish-yellow and a See also:

• ROSE
• ROSE (Rosa)
• ROSE, GEORGE (1744-1818)
• ROSE, HUGH JAMES (1795—1838)
• ROSE, WILLIAM STEWART (1775-1843)

rose-See also:

• PINK

pink . The colour in many cases is unstable, and the brown topazes of Siberia are specially liable to suffer See also:

• BLEACHING

bleaching by exposure to sunlight . In 1750 a Parisian jeweller named Dumelle discovered that the yellow Brazilian topaz becomes pink on exposure to a moderate See also:

• HEAT (0. E. haktu, which like " hot," Old Eng. hat, is from the Teutonic type haita, hit, to be hot; cf. Ger. hitze, heiss; Dutch, hitte, heet, &c.)

heat, and this treatment has since been extensively applied, so that nearly all the pink topaz occurring in See also:

• JEWELRY (O. Fr. jouel, Fr. joyau, perhaps from joie, joy; Lat. gaudium; retranslated into Low Lat. jocale, a toy, from jocus, by misapprehension of the origin of the word)

jewelry has been artificially heated . Such " burnt topaz " is often known as " Brazilian See also:

• RUBY (Lat. rubeus, red)

ruby," a name applied also to the natural red topaz, which, however, is excessively rare . " Brazilian See also:

• SAPPHIRE

sapphire " is the See also:

• TERM

term sometimes given to blue topaz, but the colour is usually See also:

• PALE (through Fr. pal, from Lat. palms, a stake, for paglus, from the stem pag- of pangere, to fix; " pole " is from the same original source)

pale . The delicate See also:

• GREEN, A
• GREEN, ALEXANDER HENRY (1832—1896)
• GREEN, DUFF (1791—1875)
• GREEN, JOHN RICHARD (1837—1883)
• GREEN, MATTHEW (1696-1737)
• GREEN, THOMAS HILL (1836-1882)
• GREEN, VALENTINE (1739–1813)
• GREEN, WILLIAM HENRY (.1825–1900)

green topaz has been incorrectly called See also:

• AQUAMARINE (Lat. aqua marina, " water of the sea ")

aquamarine, which is a name applicable only to the sea-green See also:

• BERYL

beryl (q.v.) . According to A . K . Coomfiraswamy, yellow sapphire is often sold as topaz in See also:

• CEYLON

Ceylon, where yellow topaz is unknown, whilst pink See also:

• CORUNDUM

corundum is frequently called there " See also:

• KING
• KING (O. Eng. cyning, abbreviated into cyng, cing; cf. O. H. G. chun- kuning, chun- kunig, M.H.G. kiinic, kiinec, kiinc, Mod. Ger. Konig, O. Norse konungr, kongr, Swed. konung, kung)
• KING [OF OCKHAM], PETER KING, 1ST BARON (1669-1734)
• KING, CHARLES WILLIAM (1818-1888)
• KING, CLARENCE (1842–1901)
• KING, EDWARD (1612–1637)
• KING, EDWARD (1829–1910)
• KING, HENRY (1591-1669)
• KING, RUFUS (1755–1827)
• KING, THOMAS (1730–1805)
• KING, WILLIAM (1650-1729)
• KING, WILLIAM (1663–1712)

king topaz." The topaz is cut on a leaden See also:

• WHEEL (0. Eng. hweol, hweohl, &c., cognate with Icel. hjol, Dan. hiul, the Indo-European root is seen in Sanskrit chakra, Gr. r in Aos, circle, whence " cycle ")
• WHEEL, BREAKING ON THE

wheel, and polished with See also:

• TRIPOLI
• TRIPOLI (Tarabulus el-Gharb, i.e. Tripoli of the West)
• TRIPOLI, or TARABULUS (anc. Tripolis)

tripoli .

It is generally step-cut, or table-cut, but its beauty is best See also:

• DEVELOPED

developed when in the See also:

• FORM (Lat. forma)

form of a brilliant . Cut topazes of large See also:

• SIZE

size are known, and it is said that the See also:

• GREAT

great " See also:

• BRAGANZA (Braganca)

Braganza diamond " of See also:

• PORTUGAL

Portugal is probably a topaz . Topaz usually occurs in granitic and gneissose rocks, often in See also:

• GREISEN (in French, hyalomicte)

greisen, and is commonly associated with cassiterite, See also:

• TOURMALINE

tourmaline and beryl . It seems to have been formed, in many cases, by pneumatolytic See also:

• ACTION

action . In the See also:

• WEST
• WEST, BENJAMIN (1738-1820)
• WEST, NICHOLAS (1461-1533)

west of England it is found in See also:

• CORNWALL

Cornwall, notably at St See also:

• MICHAEL
• MICHAEL (1596-1645)
• MICHAEL (Hebrew Sn,q, " Who is like God? ")

Michael's See also:

• MOUNT, WILLIAM SIDNEY (1807-1868)

Mount and at Cligga See also:

• HEAD (in 0. Eng. heafad; the word is common to Teutonic languages; cf. Dutch hoofd, Ger. Haupt, generally taken to be in origin connected with Lat. caput, Gr. KerbOvi7)
• HEAD, SIR EDMUND WALKER, BART
• HEAD, SIR FRANCIS BOND, BART

Head near St See also:

• AGNES, SAINT

Agnes . It occurs also in See also:

• LUNDY
• LUNDY, BENJAMIN (1789-1839)
• LUNDY, ROBERT (fl. 1688)

Lundy Island . The finest See also:

• BRITISH

British topaz is found in the See also:

• CAIRNGORM

Cairngorm See also:

• GROUP

group of mountains in the central See also:

• HIGHLANDS, THE

Highlands, especially at See also:

• BEN (from Old Eng. bennan, within)

Ben a Buird . Rolled pebbles occur in the See also:

• BED
• BED (a common Teutonic word, cf. German Bett, probably connected with the Indo-European root bhodh, seen in the Lat. fodere, to dig; so " a dug-out place " for safe resting, or in the same sense as a garden " bed ")

bed of the See also:

• AVON

Avon in See also:

• BANFFSHIRE

Banffshire . Beautiful, though small, crystals occur in the drusy cavities of the See also:

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

granite of the Mourne Mountains in See also:

• IRELAND
• IRELAND, CHURCH
• IRELAND, CHURCH OF
• IRELAND, JOHN (1761-1842)
• IRELAND, JOHN (1838- )
• IRELAND, WILLIAM HENRY (1777-1835)

Ireland . The famous topaz-rock of the Schneckenstein, near See also:

• AUERBACH, BERTHOLD (1812-1882)

Auerbach, in Saxony, yields pale yellow crystals, formerly cut for jewelry, and it is said that these do not become pink on heating . Fine topazes occur in See also:

• RUSSIA
• RUSSIA (Rossiya)

Russia, at several localities in the Urals and in the Adun-chalon Mountains, near See also:

• NERCHINSK
• NERCHINSK (in full NERCHINSKIY ZAVOD)

Nerchinsk, in Siberia . A very fine See also:

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

series from the See also:

• KOKSHAROV, NIKOLAI IVANOVICH VON (1818–1893)

Koksharov collection is in the British Museum .

Beautiful crystals of topaz are found in See also:

• JAPAN

Japan, especially at Takayama in the See also:

• PROVINCE
• PROVINCE (Lat. provincia; perhaps a contraction of providentia)

province of Mino, and at Tanokamiyama in Omi province . Ceylon and See also:

• BURMA

Burma occasionally yield topazes . Brazil is a famous locality, the well-known sherry-yellow crystals coming from Ouro Preto, formerly called See also:

• VILLA

Villa Rica, the See also:

• CAPITAL (i.e. capital stock or fund)
• CAPITAL (Lat. caput, head)

capital of Minas Geraes, where they occur in a kaolinitic See also:

• MATRIX

matrix, resulting from the alteration of a See also:

• MICA

mica-schist, which is regarded by Professor O . A . See also:

• DERBY
• DERBY, EARLS OF

Derby as a metamorphosed igneous rock . Topaz occurs in the See also:

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

tin-drifts of New See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South See also:

• WALES (Cymru, Gwalia, Cambria)

Wales, especially in the New England See also:

• DISTRICT

district; it has been discovered in the See also:

• COOLGARDIE

Coolgardie See also:

• GOLDFIELD

goldfield, West See also:

• AUSTRALIA

Australia; and it is found also in the tinfields of See also:

• TASMANIA

Tasmania and on See also:

• FLINDERS, MATTHEW (1774-1814)

Flinders Island in See also:

• BASS
• BASS (the same word as " base," and so pronounced, but influenced in spelling by the Ital. basso)

Bass's Strait . Fine topaz has been worked near See also:

• PIKE
• PIKE, ZEBULON MONTGOMERY (1779-1813)

Pike's See also:

• PEAK, THE

Peak in See also:

• COLORADO

Colorado, and in See also:

• SAN

San Diego See also:

• COUNTY (through Norm. Fr. comae, cf. O. Fr. cunte, conk', Mod. Fr. comae, from Lat. comitatus, cf. Ital. comitato, Prov. comtat; see COUNT)

county, See also:

• CALIFORNIA
• CALIFORNIA, LOWER (Baja California)
• CALIFORNIA, UNIVERSITY OF

California . The mineral occurs in See also:

• RHYOLITE (Gr. peiv, to flow, because of the frequency with which they exhibit fluxion structures)

rhyolite at Nathrop in See also:

• CHAFFEE, ADNA ROMANZA (1842- )

Chaffee county and See also:

• CHALK

Chalk See also:

• MOUNTAIN (0. Fr. montaigne; popular Lat. montanea, an adjectival form from the classical mons, montis, whence Eng. " mount," a form usually used along with the name of an individual mountain, e.g. Mt Everest)
• MOUNTAIN, THE (La Montagne)

Mountain in See also:

• SUMMIT

Summit county, Colorado, and in See also:

• TRACHYTE (Gr. rpaxus, rough)

trachyte near See also:

• SEVIER, JOHN (1745-1815)

Sevier See also:

• LAKE
• LAKE, GERARD LAKE, 1ST VISCOUNT (1744-1808)

Lake, See also:

• UTAH

Utah . The occurrence of topaz in these volcanic rocks is very notable, and contrasts with its See also:

• COMMON

common occurrence in granites . It is found in like manner in rhyolite at San Luis See also:

• POTOSI

Potosi in See also:

• MEXICO
• MEXICO (Span. Mejico, or Mexico,)
• MEXICO, FEDERAL DISTRICT OF
• MEXICO, GULF OF

Mexico; and beautiful little limpid crystals accompany stream-tin at See also:

• DURANGO

Durango . Common topaz occurs in coarse crystals at many localities . A columnar variety from the tin-districts of Saxony and Bohemia, and from Mt Bischoff in Tasmania, is known as pycnite (amcvbs, dense) ; whilst a coarse opaque topaz from granite near See also:

• FALUN

Falun, in See also:

• SWEDEN
• SWEDEN [Sverige]
• SWEDEN, NORWAY AND

Sweden, has been termed pyrophysalite (aup, See also:

• FIRE (in O. Eng. f j'r; the word is common to West German languages, cf. Dutch vuur, Ger. Feuer; the pre-Teutonic form is seen in Sanskrit pu, pavaka, and Gr. irup; the ultimate origin is usually taken to be a root meaning to purify, cf. Lat. purus)

fire; ¢uvaw, to See also:

• BLOW, JOHN (1648-1708)

blow), in allusion to its behaviour when heated .

" See also:

• ORIENTAL

Oriental topaz " is the name sometimes given to yellow corundum, a mineral readily distinguished from true topaz by See also:

• SUPERIOR

superior hardness and See also:

• DENSITY (Lat. densus, thick)

density . Yellow and See also:

• SMOKE (from O. Eng. smeocan, to smoke, reek, cf. Dutch meek, Ger. Schmauch, probably allied to Gr. vol9caiv)

smoke-tinted See also:

• QUARTZ

quartz, or cairngorm, is often known as " Scotch topaz " or " See also:

• SPANISH

Spanish topaz," according to its locality; but these, on the contrary, are inferior in hardness and density . The See also:

• CHIEF (from Fr. chef, head, Lat. caput)

chief See also:

• DIFFERENCES, CALCULUS OF (Theory of Finite Differences)

differences between the three minerals may be seen in the following table, in which they are arranged in See also:

• ORDER
• ORDER (through Fr. ordre, for earlier ordene, from Lat. ordo, ordinis, rank, service, arrangement; the ultimate source is generally taken to be the root seen in Lat. oriri, rise, arise, begin; cf. " origin ")
• ORDER, HOLY

order of hardness, density and refractivity: Scotch True Oriental Topaz . Topaz . Topaz . Hardness . . 7 8 9 Specific gravity . . 2.6 3'5 4 Refractive indices 1.54, I.55 I.61, I.62 I.76, I.77 See also:

• CRYSTALLIZATION

Crystallization Hexagonal Orthorhombic Hexagonal Chemical composition SiO2 Al2F2SiO4 Al2Os (F . W .