PYROPHYLLITE  , a See also:

• MINERAL

mineral See also:

• SPECIES

species belonging to the 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 See also:

• FAMILY

family, and composed of hydrous See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium silicate See also:

• HAL

HAl (SiO3)2 . It occurs in two more or less distinct varieties, namely, as crystalline folia and as compact masses; distinct crystals are not known . The folia have a pronounced pearly lustre, owing to the presence of a perfect cleavage parallel to their surfaces: they are flexible but not elastic, and are usually arranged radially in See also:

• FAN (Lat. vannus; Fr. eventail)

fan-like or spherical See also:

• GROUPS
• GROUPS, THEORY

groups . This variety, when heated before the See also:

• BLOWPIPE

blowpipe, exfoliates and swells up to many times its See also:

• ORIGINAL

original See also:

• VOLUME

volume, hence the name pyrophyllite, from the See also:

• GREEK
• GREEK, ETRUSCAN AND

Greek 76p (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) and quahov (a See also:

• LEAF (O. Eng. leaf, cf. Dutch loof, Ger. Laub, Swed. lof, &c.; possibly to be referred to the root seen in Gr. Ma-eta, to peel, strip)

leaf), given by R . See also:

• HERMANN, JOHANN GOTTFRIED JAKOB (1772–1848)
• HERMANN, KARL FRIEDRICH (1804–1855)

Hermann in 1829 . The See also:

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

colour of both varieties is 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, 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 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, greyish or yellowish ; they are very soft (H . = 1–2) and are greasy to the See also:

• TOUCH (derived through Fr. toucher from a common Teutonic and Indo-Germanic root, cf. " tug," " tuck," O. H. Ger. zucchen, to twitch or draw)

touch . The specific gravity is 2.8–2.9 . The two varieties are thus very similar respectively to See also:

• TALC

talc (q.v.) and its compact variety steatite, which is, however, a hydrous See also:

• MAGNESIUM [symbol Mg, atomic weight 24.32 (0 = 16)]

magnesium H See also:

• C2H

C2H //',,,.// O \C.C6H3(OH)2 CO/`OH See also:

• C6H4
• C6H4(CH213r)2

C6H4 silicate . The compact variety of pyrophyllite is used for See also:

• SLATE (properly CLAY SLATE; in M. Eng. slat or sclat, from O. Fr. esclat, a small piece of wood used as a tile; esclater, to break into pieces, whence modern Fr. eclat, the root being seen also in Ger. schleissen, to split)

slate pencils and tailors' See also:

• CHALK

chalk (" See also:

• FRENCH
• FRENCH, DANIEL CHESTER (1850– )
• FRENCH, NICHOLAS (1604-1678)

French chalk "), and is carved by the See also:

• CHINESE, JAPANESE AND

Chinese into small images and ornaments of various kinds . Other soft compact minerals (steatite and pinite) used for these Chinese carvings are included with pyrophyllite under the terms agalmatolite and pagodite . Pyrophyllite occurs in schistose rocks, often associated with See also:

• CYANITE

cyanite, of which it is an alteration product .

Pale green foliated masses, very like talc in See also:

• APPEARANCE (from Lat. apparere, to appear)

appearance, are found at Beresovsk near See also:

• EKATERINBURG

Ekaterinburg in the Urals, and at See also:

• ZERMATT

Zermatt in See also:

• SWITZERLAND

Switzerland . The most extensive deposits are in the Deep See also:

• RIVER

river region of See also:

• NORTH
• NORTH, BARONS
• NORTH, MARIANNE (1830—1890)
• NORTH, ROGER (1653-1734)
• NORTH, SIR THOMAS (1535?-16o1?)

North Carolina, where the compact variety is See also:

• MINED

mined, and in See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South Carolina and See also:

• GEORGIA

Georgia .