Eudialyte

Eudialyte

Infobox mineral
name = Eudialyte
category =
boxwidth =
boxbgcolor =



caption =
formula = sodium15calcium6(iron,manganese)3 zirconium3siliconoxygen(oxygen,hydroxide,hydrogen2oxygen)3(silicon3oxygen9)2(silicon9oxygen27)2 (hydroxide,chlorine)2
molweight =
color = Red, magenta, brown; also blue and yellow
habit = Granular, tabular
system = Trigonal
twinning =
cleavage = [0001] Imperfect
fracture = Uneven
mohs = 5 - 5.5
luster = Vitreous
refractive = 1.598 - 1.602
opticalprop =
birefringence =
pleochroism = Weak, brown-red to red-pink to yellow
streak = White
gravity = 2.8 - 3
melt =
fusibility =
diagnostic =
solubility = H2SO4
diaphaneity = Transparent to translucent
other =

Eudialyte, whose name derives from the Greek "eu" and "dialytos", meaning "well decomposable", is a somewhat rare, red silicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites. Its name alludes to its ready solubility in acid.

Uses of eudialyte

Eudialyte is used as a minor ore of zirconium. Another use of eudialyte is as a minor gemstone, but this use is limited by its rarity, which is compounded by its poor crystal habit. These factors make eudialyte of primary interest as a collector's mineral.

Associated minerals

Eudialyte is found associated with other alkalic igneous minerals, in addition to the some minerals common to most igneous material in general. These minerals include:
*nepheline, (sodium, potassium)aluminumsiliconoxygen4
*aegirine, sodiumironsilicon2oxygen6
*natrolite, sodium2aluminum2silicon3oxygen10hydrate|2
*albite, sodiumaluminumsilicon3oxygen8

Alternative names

Alternative names of eudialyte include: almandine spar and eudalite. Eucolite is the name of an altered form.

Notes for identification

Eudialyte's rarity makes locality useful in its identification. Prominent localities of eudialyte include Mont Saint-Hilaire in Canada and the Kola Peninsula in Russia, but it is also found in Greenland, Norway, and Arkansas. The lack of crystal habit, associated with color, is also useful for identification, as are associated minerals. A pink-red mineral with no good crystals associated with other alkaline igneous material, especially nepheline and aegirine, is a good indication a specimen is eudialyte.

Eudialyte group

Microchemical (by electron microprobe) and structural analyzes of different eudialyte (and related) samples revealed presence of many new eudialyte-like minerals. These minerals are structurally and chemically related and joined into eudialyte group. The group includes Zr-,OH-, Cl-, F-, CO3- and possibly also SO4-bearing silicates of Na, K, H3O, Ca, Sr, REEs, Mn, Fe, Nb and W. Electron vacancies can be present in their structure, too.

References

* [http://www.webmineral.com/data/Eudialyte.shtml WebMineral Listing]
* [http://www.mindat.org/min-1420.html MinDat Listing]
* [http://mineral.galleries.com/minerals/silicate/eudialyt/eudialyt.htm Mineral Galleries]


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • EUDIALYTE — De formule chimique supposée: (Na, Ca)6[ZrSi618](OH, Cl), l’eudialyte possède deux variétés, l’une enrichie en FeO, l’eucolite, l’autre, intermédiaire par sa teneur en FeO, la mésodialyte. Dans le système rhomboédrique, elle cristallise en… …   Encyclopédie Universelle

  • Eudialyte — Eu*di a*lyte, n. [Gr. e y^ well, easily + ? to dissolve. So called because easily dissolvable in acids.] (Min.) A mineral of a brownish red color and vitreous luster, consisting chiefly of the silicates of iron, zirconia, and lime. [1913 Webster] …   The Collaborative International Dictionary of English

  • eudialyte — eu·di·a·lyte …   English syllables

  • eudialyte — yüˈdīəˌlīt noun ( s) Etymology: German eudialyt, from Greek eudialytos easy to dissolve, from eu + dialytos capable of being dissolved, from dialyein to dissolve more at dialysis : a mineral Na4(Ca,Fe)2ZrSi6O17(OH,Cl)2 consisting of a brownish… …   Useful english dictionary

  • Eudialyt — in Syenit aus Brasilien Chemische Formel Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2 Mineralklasse …   Deutsch Wikipedia

  • eu- — ♦ Élément, du gr. eu « bien, agréablement ». eu élément, du gr. eu, bien . ⇒EU , élément préf. Élément préf. tiré du préf. gr. (de l adv. « bien »), entrant dans la formation de mots (gén. subst.) dans des domaines sc. ou didact.; le 2e élément… …   Encyclopédie Universelle

  • Gittinsite — Gittinsite[1] Catégorie IX : silicates[2] …   Wikipédia en Français

  • List of minerals C-E (complete) — It is currently not possible to have a complete list of minerals . The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go… …   Wikipedia

  • eucolite — ● eucolite nom féminin Synonyme de eudialyte. ● eucolite (synonymes) nom féminin Synonymes : eudialyte …   Encyclopédie Universelle

  • Hafnium — lutetium ← hafnium → tantalum Zr ↑ Hf ↓ Rf …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”