See also:

• ALUNITE, or ALUMSTONE

ALUNITE, or ALUMSTONE  , a See also:

• MINERAL

mineral first observed in the 15th See also:

• CENTURY (from Lat. centuria, a division of a hundred men)

century at See also:

• TOLFA

Tolfa, near See also:

• ROME
• ROME (Roma)

Rome, where it is See also:

• MINED

mined for the manufacture of See also:

• ALUM

alum . Extensive deposits are also worked in See also:

• TUSCANY
• TUSCANY (Toscana)

Tuscany and See also:

• HUNGARY
• HUNGARY (Hungarian Magyarorszdg)

Hungary, and at Bulladelah in New See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South See also:

• WALES (Cymru, Gwalia, Cambria)

Wales . By repeatedly roasting and lixiviating the mineral, alum is obtained in See also:

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

solution, and this is crystallized out by evaporation . See also:

• ALUNITE, or ALUMSTONE

Alunite occurs as seams in trachytic and allied volcanic rocks, having been formed by the See also:

• ACTION

action of sulphureous vapours on these rocks . The 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, finely granular masses somewhat resemble See also:

• LIMESTONE

limestone in See also:

• APPEARANCE (from Lat. apparere, to appear)

appearance, and the more compact kinds from Hungary are so hard and tough that they are used for millstones . Distinct crystals of alunite are rarely met with in cavities in the massive material; these are rhombohedra with interfacial angles of 9o° 50', so that they resemble cubes in appearance . See also:

• MINUTE
• MINUTE (Lat. minutes, small; minuere, to make less)

Minute glistening crystals have also been found loose in cavities in altered See also:

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

rhyolite . The hardness is 4 and the specific gravity 2.6 . The mineral is a hydrated basic See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium and See also:

• POTASSIUM [symbol K (from kalium), atomic weight 39.114 0=16)]

potassium sulphate, KAl3(SO4)2(OH)5 . It is insoluble in See also:

• WATER

water, but soluble in sulphuric See also:

• ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid . First called aluminilite by J . C .

Delametherie in 1797, this name was contracted by F . S . See also:

• BEUDANT, FRANCOIS SULPICE (1787—1850)

Beudant in 1824 to alunite . (L . J .