Davidite

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Davidite-(La)
Davidite-(La)-35242.jpg
Davidite-(La) from Kazakhstan
General
Category Oxide minerals
Formula
(repeating unit)
(La,Ce,Ca)(Y,U)(Ti,Fe3+)20O38
Strunz classification 04.CC.40
Crystal symmetry Trigonal rhombohedral (3)
Unit cell a = 10.376 Å, c = 20.91 Å; Z = 3
Identification
Color Black
Crystal system Trigonal
Fracture Subconchoidal to uneven
Tenacity Brittle
Mohs scale hardness ~6
Luster Vitreous
Diaphaneity Opaque, translucent in very thin fragments
Specific gravity 4.33 to 4.48
Alters to Metamict
References [1][2][3][4]

Davidite is a rare earth oxide mineral with chemical end members La and Ce. It exists in two forms:

References[edit]

  1. ^ Davidite-La in Handbook of Mineralogy
  2. ^ Davidite-La on Mindat
  3. ^ Davidite-(La) on Webmineral
  4. ^ Davidite-(Ce) on Webmineral
  5. ^ Branagan, D.F. (2005): T.W. Edgeworth David: A Life: Geologist, Adventurer and "Knight in the Old Brown Hat", National Library of Australia, Canberra, p. 471. ISBN 0 642 10791 2