View source for Malachite

{{Other uses}}
{{Infobox mineral
| name        = Malachite 
| category    = [[Carbonate mineral]]
| boxwidth    = 
| boxbgcolor  = 
| image       = Malachite, Zaire.jpg
| caption     = Malachite from the Congo
| formula     = Cu<sub>2</sub>CO<sub>3</sub>(OH)<sub>2</sub>
| molweight   = 221.1 g/mol
| strunz      = 05.BA.10
| color       = Bright green, dark green, blackish green, commonly banded in masses; green to yellowish green in transmitted light
| habit       = Massive, botryoidal, stalactitic, crystals are acicular to tabular prismatic
| system      = [[Monoclinic]]—prismatic H-M Symbol (2/m) [[Space group]] P2<sub>1</sub>/a
| twinning    = Common as contact or penetration twins on {100} and {201}. Polysynthetic twinning also present.
| cleavage    = Perfect on {{{overline|2}}01} fair on {010}
| fracture    = Subconchoidal to uneven
| mohs        = 3.5–4.0
| luster      = Adamantine to vitreous; silky if fibrous; dull to earthy if massive
| refractive  = n<sub>α</sub> = 1.655 n<sub>β</sub> = 1.875 n<sub>γ</sub> = 1.909
| opticalprop = Biaxial (–)
| birefringence = δ = 0.254
| pleochroism = 
| streak      = light green
| gravity     = 3.6–4
| melt        = 
| fusibility  = 
| diagnostic  = 
| solubility  = 
| diaphaneity = Translucent to opaque
| other       = 
| references  = <ref name=Handbook>[http://rruff.geo.arizona.edu/doclib/hom/malachite.pdf Malachite in Handbook of Mineralogy]</ref><ref>[http://webmineral.com/data/Malachite.shtml Malachite at Webmineral]</ref><ref name=Mindat>[http://mindat.org/min-2550.html Malachite at Mindat]</ref>
}}

'''Malachite''' is a copper [[Carbonate mineral|carbonate]] hydroxide mineral,  with the [[chemical formula|formula]]  [[copper|Cu]]<sub>2</sub>[[carbonate|CO<sub>3</sub>]][[hydroxide|(OH)]]<sub>2</sub>. This green-colored mineral  crystallizes in the [[monoclinic]] crystal system, and most often forms [[botryoidal]], fibrous, or [[stalagmite|stalagmitic]] masses, in fractures and spaces, deep underground, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare but do occur as slender to [[Acicular (crystal habit)|acicular]] prisms.  [[Pseudomorph]]s after more tabular or blocky [[azurite]] crystals also occur<ref name=Mindat/>. Typical malachite is laminated and whether or not microbes intervene in its formation is unknown.

==Etymology and history==
The stone's name derives (via [[Latin]]: ''molochītis'', [[Middle French]]: ''melochite,'' and [[Middle English]] ''melochites'') from [[Greek language|Greek]] ''Μολοχίτης λίθος'' ''molochitis lithos'', "mallow-green stone", from ''μολόχη'' ''molōchē'', variant of ''μαλάχη'' ''malāchē'', "mallow".<ref>[http://dictionary.reference.com/browse/Malachite Malachite], Dictionary.com</ref> The mineral was given this name due to its resemblance to the leaves of the [[Malva|Mallow plant]].<ref>{{OEtymD|malachite}}</ref>

Malachite was used as a mineral pigment in green paints from antiquity until about 1800. The pigment is moderately lightfast, very sensitive to [[acid]]s and varying in color. The natural form was being replaced by its synthetic form, [[verditer]] amongst other synthetic greens.  It is also used for decorative purposes, such as in the Malachite Room in the [[Hermitage Museum|Hermitage]], which features  "The [[Tazza]]", a large malachite vase and one of the largest pieces of malachite in North America. A gift from [[Tsar Nicholas II]], it stands as the focal point in the center of the room of [[Linda Hall Library]].

Archeological evidence indicates that the mineral has been mined and smelted at [[Timna valley]] in [[Israel]] for over 3,000 years.<ref>Parr, Peter J review of "Timma: Valley of the Biblical Copper Mines" by Beno Rothenberg Bulletin of the School of Oriental and African Studies, University of London, Vol. 37, No. 1, In Memory of W. H. Whiteley (1974), pp. 223–224</ref>

==Occurrence==
Malachite often results from weathering of [[copper]] [[ore]]s and is often found together with [[azurite]] (Cu<sub>3</sub>(CO<sub>3</sub>)<sub>2</sub>(OH)<sub>2</sub>), [[goethite]], and [[calcite]]. Except for its vibrant green color, the properties of malachite are  similar to those of azurite and aggregates of the two minerals occur frequently.  Malachite is more common than [[azurite]] and is typically associated with copper deposits around [[limestone]]s, the source of the carbonate.

Large quantities of malachite have been mined in the [[Urals]], [[Russia]]. It is found worldwide including in the [[Democratic Republic of Congo]]; [[Gabon]]; [[Zambia]]; [[Tsumeb]], [[Namibia]]; [[Mexico]]; [[Broken Hill, New South Wales]]; [[Lyon]], [[France]]; [[Timna valley]], [[Israel]], and in the Southwestern [[United States]] notably in [[Arizona]].<ref>[http://www.mindat.org/show.php?id=2550&ld=1#themap Mindat map with over 8500 locations]</ref> 

==Malachite gallery==
<gallery  widths="150px" heights="150px" perrow="3">>
File:Malachite-41365.jpg|Slice through a double [[stalactite]], from [[Kolwezi]], [[Democratic Republic of Congo]]. Size 5.9 × 3.9 × 0.7 cm.
File:Malachite Kolwezi Katanga Congo.jpg|A polished slab of malachite, from the [[Democratic Republic of Congo]]
File:Malachite-unit-cell-3D-balls.png|[[Ball-and-stick model]] of malachite's [[unit cell]]
File:Azurite-Malachite-59275.jpg|Malachite and [[azurite]], from [[Morenci, Arizona]] USA. Size 4.4×4.1×2.2 cm.
File:Malachite-153552.jpg|Malachite stalactites (to 9 cm height), from Kasompi Mine, [[Katanga Province]], [[Democratic Republic of Congo]]. Size: 21.6×16.0×11.9 cm.
File:Malachite-azmex10a.jpg|[[Botryoidal]] malachite from [[Bisbee, Arizona]] USA. Size 10.5×6.3×5.6 cm.
File:Ermitáž.jpg|Neoclassical vase in malachite in the [[Hermitage Museum]], St Petersburg
</gallery>

==See also==
*[[Aventurine#Aventurine|Aventurine]]
*[[Azurite]]
*[[Brochantite]]
*[[Chrysocolla]]
*[[Dioptase]]
*[[Plancheite]]

==References==
{{Reflist|2}}

==Further reading==
{{Wiktionary}}
{{Commons category}}
* Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., John Wiley and Sons, New York ISBN 0-471-80580-7.
* [http://hermitagemuseum.org/html_En/08/hm88_0_1_62.html Virtual tour of the Malachite Room]

{{Jewelery}}

[[Category:Carbonate minerals]]
[[Category:Copper minerals]]
[[Category:Gemstones]]
[[Category:Monoclinic minerals]]

[[ar:مالاكايت]]
[[az:Malaxit]]
[[be:Малахіт]]
[[bg:Малахит]]
[[bs:Malahit]]
[[br:Malakit]]
[[ca:Malaquita]]
[[cs:Malachit]]
[[da:Malakit]]
[[de:Malachit]]
[[et:Malahhiit]]
[[el:Μαλαχίτης]]
[[es:Malaquita]]
[[eo:Malakito]]
[[eu:Malakita]]
[[fa:مالاکیت]]
[[fr:Malachite]]
[[gl:Malaquita]]
[[ko:공작석]]
[[hi:ताप्रांगीयिज]]
[[hr:Malahit]]
[[io:Malakito]]
[[is:Malakít]]
[[it:Malachite]]
[[he:מלכיט]]
[[ka:მალაქიტი]]
[[kk:Малахит]]
[[la:Malachites]]
[[lt:Malachitas]]
[[hu:Malachit]]
[[ms:Malakit]]
[[nl:Malachiet]]
[[ja:孔雀石]]
[[pl:Malachit]]
[[pt:Malaquita]]
[[ro:Malachit]]
[[ru:Малахит]]
[[sk:Malachit]]
[[sl:Malahit]]
[[sh:Malahit]]
[[fi:Malakiitti]]
[[sv:Malakit]]
[[th:มาลาไคต์]]
[[tr:Malahit]]
[[uk:Малахіт]]
[[ug:يېشىل تاش]]
[[vi:Malachit]]
[[zh-yue:石綠]]
[[zh:碱式碳酸铜]]