BARYTES  , a widely distributed See also:

• MINERAL

mineral composed of See also:

• BARIUM (symbol Ba, atomic weight 137'37 [0=16])

barium sulphate (BaSO4) . Its most striking feature and the one from which it derives its name barytes, barite (from the See also:

• GREEK
• GREEK, ETRUSCAN AND

Greek Oapvs, heavy) or heavy spar, is its See also:

• WEIGHT

weight . Its specific gravity of 4.5 is about twice as See also:

• GREAT

great as that of See also:

• SALT (a common Teutonic word, cf. Dutch zout, Ger. Salz, Scand. salt; cognate with Gr. &Xs, Lat. sal)
• SALT, SIR TITUS, BART

salt and of many other colourless, transparent and glassy minerals not unlike barytes in See also:

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

general See also:

• APPEARANCE (from Lat. apparere, to appear)

appearance . The mineral is usually found in a See also:

• STATE
• STATE, GREAT OFFICERS OF

state of consider-able chemical purity, though small amounts of See also:

• STRONTIUM [Symbol Sr, atomic weight 87.62 (0=16)]

strontium and See also:

• CALCIUM [symbol Ca, atomic weight 40.0 (o= x6)]

calcium sulphates may isomorphously replace the barium sulphate: ammonium sulphate is also sometimes See also:

• PRESENT

present, whilstclay, See also:

• SILICA

silica, bituminous See also:

• MATTER

matter, &c., may be enclosed as impurities . Crystals of barytes are orthorhombic and isomorphous with the strontium and See also:

• LEAD
• LEAD (pronounced iced)

lead sulphates (celestite and anglesite) ; they are usually very perfectly See also:

• DEVELOPED

developed and present great variety of See also:

• FORM (Lat. forma)

form . The simplest are rhomb-shaped tables (fig . 1) bounded by the two faces of the basal pinacoid (c) and the four faces of the See also:

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

prism (m); the See also:

• ANGLE (from the Lat. angulus, a corner, a diminutive, of which the primitive form, angus, does not occur in Latin; cognate are the Lat. angere, to compress into a bend or to strangle, and the Gr. ayKOS, a bend; both connected with the Aryan root ank-, to

angle between the prism-faces (mm) is 78° 23', whilst that between c and m is 9o° . The mineral has a very perfect cleavage parallel to the faces c and m, and the cleavage surfaces are perfectly smooth and See also:

• BRIGHT, JOHN (1811-188g)
• BRIGHT, SIR CHARLES TILSTON

bright . The crystals of 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 represented in See also:

• FIGS

figs . 2 and 3 are bounded by the domes d and f and the basal pinacoid c; fig . 4 is a See also:

• PLAN
• PLAN (from Lat. planes, flat)

plan of a still A%:: ~ .~ Gw --------------------- more complex crystal . Twinning is represented only by twin-lamellae, which are parallel to the planes m and f and are of secondary origin, having been produced by pressure .

Crystals of barytes may be transparent and colourless, or See also:

• WHITE
• WHITE, ANDREW DICKSON (1832– )
• WHITE, GILBERT (1720–1793)
• WHITE, HENRY KIRKE (1785-1806)
• WHITE, HUGH LAWSON (1773-1840)
• WHITE, JOSEPH BLANCO (1775-1841)
• WHITE, RICHARD GRANT (1822-1885)
• WHITE, ROBERT (1645-1704)
• WHITE, SIR GEORGE STUART (1835– )
• WHITE, SIR THOMAS (1492-1567)
• WHITE, SIR WILLIAM ARTHUR (1824--1891)
• WHITE, SIR WILLIAM HENRY (1845– )
• WHITE, THOMAS (1628-1698)
• WHITE, THOMAS (c. 1550-1624)

white and opaque, or of a yellow, 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, bluish or greenish See also:

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

colour . Well developed crystals are extremely See also:

• COMMON

common, but the mineral occurs also in a granular, earthy, or stalactitic See also:

• CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)

condition . It is known as cawk in the See also:

• DERBYSHIRE

Derbyshire lead mines . The " crested " or " See also:

• COCK, EDWARD (1805-1892)

cock's See also:

• COMB (a word common in various forms to Teut. languages, cf. Ger. Kamm, the Indo-Europ. origin of which is seen in yoµros, a peg or pin, and Sanskrit, gambhas, a tooth)

comb " barytes occurs as rounded aggregations of thin lamellar crystals . Barytes is of common occurrence in metalliferous See also:

• VEINS

veins, especially those which yield ores of lead and See also:

• SILVER

silver; some of the largest and most perfect crystals of colourless barytes were obtained from the lead mines near Duf ton in See also:

• WESTMORLAND
• WESTMORLAND, EARLS OF

Westmorland . It is found also in beds of See also:

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

iron ore, and the See also:

• HAEMATITE, or HEMATITE

haematite mines of the Cleator See also:

• MOOR

Moor See also:

• DISTRICT

district in See also:

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

west See also:

• CUMBERLAND
• CUMBERLAND, DUKES AND EARLS OF
• CUMBERLAND, RICHARD (1632-1718)
• CUMBERLAND, RICHARD (1732-1811)
• CUMBERLAND, WILLIAM AUGUSTUS

Cumberland have yielded many extremely See also:

• FINE

fine crystals, specimens of which may be seen in all mineral collections . In the neighbourhood of See also:

• NOTTINGHAM
• NOTTINGHAM, CHARLES HOWARD, 1ST EARL OF1 (1536-1624)
• NOTTINGHAM, EARLS OF

Nottingham, and other places in the Midlands, barytes forms a cementing material in the Triassic sandstones; See also:

• AMBER

amber-coloured crystals of the same mineral are found in the See also:

• FULLER, ANDREW (1954-1815)
• FULLER, GEORGE (1822—1884)
• FULLER, M
• FULLER, MARGARET, MARCHIONESS
• FULLER, MELVILLE WESTON (1833-1910)
• FULLER, THOMAS (16o8-1661)
• FULLER, WILLIAM (1670--c. 1717)

fuller's See also:

• EARTH
• EARTH (a word common to Teutonic languages, cf. Ger. Erde, Dutch aarde, Swed. and Dan. jord; outside Teutonic it appears only in the Gr. 'pq'e, on the ground; it has been connected by some etymologists with the Aryan root ar-, to plough, which is seen in
• EARTH, FIGURE OF
• EARTH, FIGURE OF THE

earth at Nutfield in See also:

• SURREY
• SURREY, EARLDOM OF
• SURREY, HENRY HOWARD, EARL OF (1518?-1547)

Surrey; and the septarian nodules in See also:

• LONDON

London See also:

• CLAY (from O. Eng. claeg, a word common in various forms to Teutonic languages, cf. Ger. Klei)
• CLAY, CASSIUS MARCELLUS (1810-1903)
• CLAY, CHARLES (1801–1893)
• CLAY, FREDERIC (1838–1889)
• CLAY, HENRY (1777–1852)

Clay contain crystals of barytes as well as of See also:

• CALCITE

calcite . Crystals are found as a rarity in the amygdaloidal cavities of igneous rocks . Artificially prepared crystals of barytes may be obtained by allowing a See also:

• SOLUTION (from Lat. solvere, to loosen, dissolve)

solution of a soluble barium salt to diffuse slowly into a solution of a soluble sulphate . Barium chloride is present in some natural See also:

• WATERS, TERRITORIAL

waters, and when this is the See also:

• CASE
• CASE, JOHN (d. 1600)

case the interaction of sulphates results in a deposition of barytes, as has occurred in the pipes and See also:

• WATER

water-boxes of the See also:

• NEWCASTLE
• NEWCASTLE, DUKES OF

Newcastle-on-See also:

• TYNE

Tyne See also:

• COAL

coal mines . Commercially, barytes is used in the preparation of barium compounds, as a See also:

• BODY

body for certain kinds of See also:

• PAPER
• PAPER (Fr. papier, from Lat. papyrus)

paper and See also:

• CLOTH

cloth, and as a white pigment (" permanent white ") . The finely powdered and washed mineral is too crystalline and consequently of insufficient opacity to be used alone as a paint, and is therefore mixed with " white lead," of which material it is also used as an adulterant .

(L . J .