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BOROLANITE , one of the most remarkable rocks of the See also:British Isles, found on the shores of See also:Loch Borolan in See also:Sutherland-'See also:shire, after which it has been named. In this locality there is a considerable See also:area of See also:granite See also:rich in red See also:alkali See also:felspar, and passing, by diminution in the amount of its See also:quartz, into quartz-syenites (nordmarkites) and syenites. At the margins of the outcrop patches of See also:nepheline-See also:syenite occur; usually the nepheline is decomposed, but occasionally it is well-preserved; the other ingredients of the See also:rock are 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 See also:garnet (melanite) and aegirine. The abundance of melanite is very unusual in igneous rocks, though some syenites, leucitophyres, and aegirine-felsites resemble borolanite in this respect. In places the nephelinesyenite assumes the See also:form of a dark rock with large rounded 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 spots. These last consist of an intermixture of nepheline or See also:sodalite and alkali-felspar. From the See also:analogy of certain leucitesyenites which are known in See also:Arkansas, it is very probable that these spots represent See also:original leucites which have been changed into aggregates of the above-named minerals. They resemble See also:leucite in their shape, but have not yet been proved to have its crystalline outlines. The " pseudo-leucites," as they have been called, measure one-See also:quarter to three-quarters of an See also:inch across. The dark See also:matrix consists of See also:biotite, aegirine-See also:augite and melanite. Connected with the borolanite there are other types of nepheline-syenite and See also:pegmatite. In See also:Finland, melanitebearing nepheline rocks have been found and described as See also:Ijolite, but the only other locality for melanite-leucite-syenite is Magnet See also:Cove in Arkansas.
(J. S.
End of Article: BOROLANITE
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