Metatorbernite
4079732
216240313
2008-05-31T19:22:52Z
Pere prlpz
2176094
[[ca:Meta-torbernita]]
{{Infobox mineral
| name = Metatorbernite
| category =
| boxwidth =
| boxbgcolor =
| image = Metatorbernite.jpg
| caption = Green platy crystals on [[granite]]
| formula = [[Copper|Cu]]([[Uranium|U]][[Oxygen|O]]<sub>2</sub>)<sub>2</sub><!--
-->([[Phosphorus|P]][[Oxygen|O]]<sub>4</sub>)<sub>2</sub>ยท<!--
-->8([[Hydrogen|H]]<sub>2</sub>[[Oxygen|O]])
| molweight =
| color = Light to dark green
| habit = Flat plates
| system = [[Tetragonal]]-dipyramidal
| twinning =
| cleavage = Perfect
| fracture = Brittle
| mohs = 2.5
| luster = Vitreous, adamantine
| refractive = 1.624-1.626
| opticalprop =
| birefringence =
| pleochroism =
| streak = Light green
| gravity = 3.7-3.8
| melt =
| fusibility =
| diagnostic =
| solubility =
| diaphaneity =
| other = [[Image:Radioactive.svg|25px]] [[Radioactive]]
}}
'''Metatorbernite''' (or '''meta-torbernite''') is a [[radioactive decay|radioactive]] [[phosphate minerals|phosphate mineral]], and is a [[dehydration]] [[pseudomorph]] of [[torbernite]]. Chemically, it is a [[copper]] [[uranyl]] [[phosphate]] and usually occurs in the form of green platy deposits. It can form by direct deposition from a [[supersaturation|supersaturated]] solution, which produces true crystalline metatorbernite, with a dark green colour, translucent [[diaphaneity]], and vitreous lustre. However, more commonly, it is formed by the dehydration of torbernite, which causes internal stress and breakage within the [[crystal structure|crystal lattice]], resulting in crystals composed of microscopic powder held together using [[Electrostatics|electrostatic]] force, and having a lighter green colour, opaque diaphaneity, and a relatively dull lustre. As with torbernite, it is named after the [[Sweden|Swedish]] [[chemist]] [[Tornbern Bergmann]]. It is especially closely associated with torbernite, but is also found amongside [[autunite]], [[meta-autunite]] and [[uraninite]].
[[Image:Metatorbernite with autunite.jpg|left|thumb|200px|Green metatorbernite with yellow autunite deposits on granite]]
==References==
*[http://www.mindat.org/min-2689.html MinDAT]
*[http://webmineral.com/data/Metatorbernite.shtml Webmineral]
*[http://www.uraniumminerals.com/UTh/M-Torbernite.htm Uranium minerals]
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{{mineral-stub}}
[[Category:Uranium minerals]][[Category:Copper minerals]][[Category:Phosphate minerals]]
[[ca:Meta-torbernita]]
[[it:Metatorbernite]]
[[hu:Metatorbernit]]