Online Encyclopedia

size, and its corners are each replaced by three small triangular faces representing the icositetrahedron (fig. 2). Although cubic in form, analcite usually shows feeble See also:

double See also:

refraction, and is thus optically anomalous. This feature of analcite has been much studied, See also:

Sir See also:

David See also:

Brewster in 1826 being the earliest investigator. Crystals of analcite are often perfectly colourless and transparent with a brilliant glassy lustre, but some are opaque and See also:

white or pinkish-white. The hardness of the mineral is 5 to 52, and its specific gravity is 2.25. Chemically, analcite is a hydrated See also:

SODIUM [symbol Na, from Lat. natrium; atomic weight 23.00 (0=16)]

sodium and See also:

ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium silicate, NaAlSi2Os+See also:

H2O (combined)

H2O; small amounts of the sodium being sometimes replaced by See also:

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

calcium or by See also:

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

potassium. The See also:

WATER

water of See also:

CRYSTALLIZATION

crystallization is readily expelled by See also:

HEAT (0. E. haktu, which like " hot," Old Eng. hat, is from the Teutonic type haita, hit, to be hot; cf. Ger. hitze, heiss; Dutch, hitte, heet, &c.)

heat, with modification of the See also:

OPTICAL

optical characters of the crystals. Before the See also:

BLOWPIPE

blowpipe the mineral readily fuses with intumescence to a colourless See also:

glass. It is decomposed by acids with separation of gelatinous See also:

SILICA

silica.

Analcite usually occurs, associated with other zeolitic minerals, lining amygdaloidal cavities in basic volcanic rocks such as See also:

BASALT

basalt and melaphyre, and especially in such as have undergone alteration by weathering; the See also:

TERTIARY

Tertiary basalts of the See also:

north of See also:

Ireland frequently contain cavities lined with small brilliant crystals of analcite. Larger crystals of the same See also:

KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

kind are found in the basalt of the Cyclopean Islands (Scogli de' Ciclopi or Faraglioni) N.E. of See also:

CATANIA (Gr. Katane, Rom. Catinal)

Catania, See also:

SICILY (Ital. Sicilia)

Sicily. Large opaque crystals of the pinkish-white See also:

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

colour are found in cavities in melaphyre at the Seisser Alpe near Schlern in See also:

SOUTHERN

southern See also:

TIROL (or TYROL 1)

Tirol. In all such cases the mineral is clearly of secondary origin, but of See also:

LATE

late years another mode of occurrence has been recognized, analcite having been found as a See also:

PRIMARY

primary constituent of certain igneous rocks such as monchiquite and some basalts. The irregular grains, of which it has the form, had previously been mistaken for glass. Owing to the fact that analcite often crystallizes in cubes, it was See also:

long known as cubic zeolite or as cuboite. The name now in use was proposed in 1797 in the form analcime, by R. J. Hairy, in allusion to the weak (avaXtas) electrification of the mineral produced by See also:

FRICTION (from Lat. fricare, to rub)

friction. Euthallite is a compact, greenish analcite, produced by the alteration of elaeolite at various localities in the Langesund-See also:

FJORD, or FIORD

fjord in southern See also:

Norway. Eudnophite, from the same region, was originally described as an orthorhombic mineral dimorphous with analcite, but has since been found to be identical with it. Cluthalite, from the See also:

Clyde (Clutha) valley, is an altered form of the mineral.

(L. J.

End of Article: ANALCITE

Additional information and Comments

There are no comments yet for this article.

» Add information or comments to this article.

Please link directly to this article:
Highlight the code below, right click, and select "copy." Then paste it into your website, email, or other HTML.

Site content, images, and layout Copyright © 2006 - Net Industries, worldwide.
Do not copy, download, transfer, or otherwise replicate the site content in whole or in part.

Links to articles and home page are always encouraged.

[back]
ANAHUAC

[next]
ANALOGY (Gr. avaXo-yLa, proportion)