See also:PHONOLITE (Gr. ~vi7, See also:sound, and Moos, 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)
, in See also:petrology, a See also:group of volcanic lavas containing much See also:nepheline and sanidine See also:felspar
.
The See also:term "clinkstone " was formerly given by geologists to many See also:fine grained compact lavas, which split into thin tough plates, and gave out a ringing See also:sound when struck with the See also:hammer
.
Some of these clinkstones were phonolites in the See also:modern sense, but as the name clinkstone was used for a large variety of rocks, many of which have no See also:close See also:affinities with one another, it has been discarded and "See also:phonolite " is substituted for it
.
The group includes rocks which are See also:rich in alkalis with only a moderate percentage of See also:silica; hence they contain no See also:free See also:quartz but much See also:alkali felspar (sanidine and anorthoclase) and nepheline
.
Large plates of sanidine are often visible in the rocks; the nepheline is usually not obvious to the unaided See also:eye
.
Most phonolites show fluxion structure, both in the See also:orientation of their phenocrysts and in the smaller crystals which make up the ground-See also:mass; and this determines to a large extent the platy jointing
.
Although vitreous and pumiceous forms are known they are rare, and in the See also:great See also:majority of cases these rocks are finely crystalline with a dull or shimmering lustre in the ground-mass
.
Marked characteristics are the readiness with which they decompose, and the frequency of See also:veins and cavities occupied by See also:natrolite, See also:analcite, See also:scolecite and other See also:zeolites
.
Small See also:black grains of See also:augite or See also:hornblende and sometimes See also:blue specks of hauyne may be seen in the rocks when they are fresh
.
The dominant minerals are sanidine, nepheline, See also:pyroxene, See also:amphibole, various felspathoids and See also:iron oxides
..
The sanidine is usually in two generations, the first consisting of large crystals of flattened and See also:tabular shape, while the second See also:generation is represented by small rectangular prisms arranged in parallel streams in the ground-mass; these felspars are nearly always simply twinned on the See also:Carlsbad See also:plan
.
They contain often as much soda as potash
.
The nepheline takes the See also:form of hexagonal prisms with See also:flat ends, and may be completely replaced by fibrous zeolites, so that it can only be recognized by the outlines of its pseudomorphs
.
In some phonolites it is exceedingly abundantmagnetite and See also:zircon occur in the phonolites, and See also:sphene is often rather See also:common
.
Another See also:mineral which is more frequent in phonolites than in many other rocks is 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 melanite See also:garnet
.
The majority of the rocks of this group are of See also:Tertiary or See also:Recent See also:age, but in See also:Scotland Carboniferous phonolites occur in several localities, e.g
.
Traprain in See also:Haddingtonshire, also in the Eildon Hills and in See also:Renfrewshire
.
In See also:Brazil phonolites belonging to the same See also:epoch are also known
.
There are several districts in See also:Europe where Tertiary or Recent phonolites occur in considerable See also:numbers, as in See also:Auvergne (Mont See also:Dore), the See also:Eifel, and Bohemia
.
The See also:Wolf See also:Rock which lies off the See also:south See also:coast of See also:Cornwall, and is the site of a well-known lighthouse, is the only mass of phonolite in See also:England; it is supposed to be the remains of a Tertiary See also:lava or intrusion
.
The See also:Canary Islands, Cape Verde Islands, See also:Sardinia, See also:Aden, See also:British See also:East See also:Africa and New See also:Zealand contain many types of phonolites; they are known also in New South See also:Wales, while in the See also:United States phonolites occur in See also:Colorado (at Cripple See also:Creek) and in the Black Hills of South Dakota
.
See also:Leucite occurs in See also:place of nepheline in a small group of phonolites (the leucite-phonolites), known principally from Rocca Monfina and other places near See also:Naples
.
Blue hauyne is rather a conspicuous mineral in some of these rocks, and they also contain a See also:good See also:deal of sphene
.
When sanidine, nepheline and leucite all occur together in a volcanic rock it is classed among the leucitophyres (see PETROLOGY, See also:Plate III. fig
.
2)
.
The chemical analyses of phonolites given below show that these rocks are very rich in alkalis and alumina with only a moderate amount of silica, while See also:lime, See also:magnesia and iron oxides are See also:present only in small quantity
.
They have a close resemblance in these respects to the nepheline-syenites of which they provide the effusive types
.
(J
.
S
.
F.)
PHORCYS•(PHORCUS, PHORCYN), in See also:Greek See also:mythology, son of See also:Pontus (See also:Sea) and Gaea (See also:Earth), See also:father of the Graeae, the Gorgons, Scylla, and Ladon (the See also:dragon that guarded the See also:golden apples of the See also:Hesperides)
.
In See also:Homer (Odyssey, xiii
.
96) he is an aged sea-deity, after whom a See also:harbour in See also:Ithaca was named
.
According to See also:Varro (quoted by Servius in Aeneid, V
.
824) Phorcys was a 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 of See also:Corsica and Sardinia, who, having been defeated by King See also:Atlas in a See also:naval engagement in the course of which he was drowned, was subsequently worshipped as a marine divinity
.
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