Jump to content

Edingtonite

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Vsmith (talk | contribs) at 13:02, 8 May 2019. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Edingtonite
Edingtonite from Ice River Alkaline Complex, Golden Mining Division, British Columbia, Canada
General
CategoryTectosilicate
Formula
(repeating unit)
BaAl2Si3O10·4H2O
Strunz classification9.GA.15
Crystal systemOrthorhombic
Identification
ColorWhite, gray, pink
Crystal habitPrismatic pseudotetragonal crystals; massive.
TwinningOn [110] and [001]
CleavagePerfect on [110]
Mohs scale hardness4 - 4.5
Specific gravity2.73 - 2.78
Optical propertiesBiaxial (-)
Refractive indexnα = 1.538 nβ = 1.549 nγ = 1.554
Birefringenceδ = 0.016
2V angle54 - 62°
Dispersionr < v; strong
Other characteristicsPyroelectric and piezoelectric
References[1][2][3]

Edingtonite is a white, gray, brown, colorless, pink or yellow zeolite mineral. Its chemical formula is BaAl2Si3O10·4H2O. It has varieties with tetragonal, orthorhombic or triclinic crystals.[4]

The mineral occurs within cavities in nepheline syenites, carbonatites, in hydrothermal veins and various mafic rocks. It occurs associated with thomsonite, analcime, natrolite, harmotome, brewsterite, prehnite and calcite.[3]

The mineral was first reported by and named for Scottish mineral collector James Edington (1787–1844).[2][3] Other sources (including the mineralogist Haidinger) credit Scottish geologist and mineralogist Thomas Edington (1814-1859).[5] However, as the mineral was named in 1825, the former accreditation must be the true one.[6]

References

  1. ^ Edingtonite mineral data from Webmineral
  2. ^ a b Edingtonite mineral data from Mindat.org
  3. ^ a b c Handbook of Mineralogy
  4. ^ Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: "Dana's new mineralogy", pp. 1683-1684. John Wiley & Sons, 1997
  5. ^ Biographical Index of Former Fellows of the Royal Society of Edinburgh 1783–2002 (PDF). The Royal Society of Edinburgh. July 2006. ISBN 0 902 198 84 X.
  6. ^ Wilhelm Karl von Haidinger, "Description of Edingtonite, a New Mineral Species", in The Edinburgh Journal of Science, V. iii, October 1825, pp. 316–320

Media related to Edingtonite at Wikimedia Commons