Editing Olivine

{{Short description|Magnesium iron silicate solid solution series mineral}}
{{Other uses}}
{{Infobox mineral
| name        = Olivine
| category    = [[Nesosilicate]]<br />Olivine group<br />Olivine series
| boxwidth    = 
| boxbgcolor  =#95bf5d 
| image       = Olivine-gem7-10a.jpg
| caption     = 
| formula     = {{chem2|(Mg,Fe)2SiO4}}
| IMAsymbol   = Ol<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3 |pages=291–320|doi=10.1180/mgm.2021.43 |bibcode=2021MinM...85..291W |s2cid=235729616 |doi-access=free}}</ref>
| strunz      = 9.AC.05
| molweight   = 
| color       = Yellow to yellow-green
| habit       = Massive to granular
| system      = [[Orthorhombic]]
| symmetry    = ''Pbnm'' (no. 62)
| twinning    = 
| cleavage    = Poor
| fracture    = [[Conchoidal fracture|Conchoidal]]
| tenacity    = brittle
| mohs        = 6.5–7.0
| luster      = Vitreous
| refractive  = ''n''<sub>α</sub> = 1.630–1.650<br />''n''<sub>β</sub> = 1.650–1.670<br />''n''<sub>γ</sub> = 1.670–1.690
| opticalprop = Biaxial (+)
| birefringence = ''δ'' = 0.040
| pleochroism = 
| streak      = colorless or white 
| gravity     = 3.2–4.5<ref name="Smith1999">{{cite book|author=Mick R. Smith|title=Stone: Building Stone, Rock Fill and Armourstone in Construction|url=https://books.google.com/books?id=Xcuoyxo33nsC&pg=PA62|year=1999|publisher=Geological Society of London|isbn=978-1-86239-029-4|pages=62–|quote=Specific Gravity 3.5–4.5}}</ref><ref name="Kogel2006">{{cite book|author=Jessica Elzea Kogel|title=Industrial Minerals & Rocks: Commodities, Markets, and Uses|url=https://books.google.com/books?id=zNicdkuulE4C&pg=PA679|year=2006|publisher=SME|isbn=978-0-87335-233-8|pages=679–|quote=The specific gravity is approximately 3.2 when pure rises with increasing iron content.}}</ref><ref>{{cite web |url=http://www.science.smith.edu/geosciences/petrology/Petrography/Olivine/Olivine.html |title=Olivine |publisher=Science.smith.edu |access-date=2013-11-14 |quote=G = 3.22 to 4.39. Specific gravity increases and hardness decreases with increasing Fe. |url-status=dead |archive-url=https://web.archive.org/web/20140120001919/http://www.science.smith.edu/geosciences/petrology/Petrography/Olivine/Olivine.html |archive-date=2014-01-20}}</ref><ref>{{cite web |url=http://www.geo.umn.edu/courses/1001/minerals/olivine.shtml |title=University of Minnesota's Mineral Pages: Olivine |publisher=Geo.umn.edu |access-date=2013-11-14 |quote=Specific Gravity: 3.2 (Mg-rich variety) to 4.3 (Iron-rich variety) (average weight) |url-status=dead |archive-url=https://web.archive.org/web/20131017062317/http://www.geo.umn.edu/courses/1001/minerals/olivine.shtml |archive-date=2013-10-17 }}</ref>
| melt        = 
| fusibility  = 
| diagnostic  = 
| solubility  = 
| diaphaneity = Transparent to translucent
| other       = 
| references  =<ref>[http://webmineral.com/data/Olivine.shtml Olivine] {{webarchive|url=https://web.archive.org/web/20141209063926/http://webmineral.com/data/Olivine.shtml |date=2014-12-09}}. Webmineral.com Retrieved on 2012-06-16.</ref><ref>[http://www.mindat.org/min-2983.html Olivine] {{webarchive|url=https://web.archive.org/web/20080202152713/http://www.mindat.org/min-2983.html |date=2008-02-02}}. Mindat.org Retrieved on 2012-06-16.</ref><ref>{{cite book
 | last = Klein
 | first = Cornelis
 | author2 = C. S. Hurlburt
 | title = Manual of Mineralogy
 | edition = 20th
 | publisher = John Wiley & Sons
 | year = 1985
 | location = New York 
 | isbn = 978-0-471-80580-9
 | url = https://archive.org/details/manualofmineralo00klei
 }}</ref>
}}

The [[mineral]] '''olivine''' ({{IPAc-en|ˈ|ɒ|l|.|ᵻ|ˌ|v|iː|n}}) is a [[magnesium]] [[iron]] [[Silicate minerals|silicate]] with the chemical formula {{chem2|auto=1|(Mg,Fe)2SiO4}}. It is a type of [[Nesosilicates|nesosilicate or orthosilicate]]. The primary component of the Earth's [[upper mantle (Earth)|upper mantle]],<ref name=DCH>{{cite book |title=Pocket Guide to the Rocks & Minerals of North America |page=23 |first=Sarah |last=Garlick |publisher=[[National Geographic Society]] |year=2014 |isbn=9781426212826}}</ref> it is a common mineral in Earth's subsurface, but weathers quickly on the surface. Olivine has many uses, such as the [[gemstone]] [[peridot]] (or chrysolite), as well as industrial applications like [[metalworking]] processes. 

[[File:Olivine in polarizing light.jpg|thumb|Olivine in cross-polarized light]]

The ratio of magnesium to iron varies between the two [[endmember (mineralogy)|endmember]]s of the [[solid solution]] series: [[forsterite]] (Mg-endmember: {{chem|[[Magnesium|Mg]]|2|[[Silicon|Si]]|[[Oxygen|O]]|4}}) and [[fayalite]] (Fe-endmember: {{chem|[[Iron|Fe]]|2|[[Silicon|Si]]|[[oxygen|O]]|4}}). Compositions of olivine are commonly expressed as [[Mole (unit)|molar]] percentages of forsterite (Fo) and/or fayalite (Fa) (''e.g.'', Fo<sub>70</sub>Fa<sub>30</sub>, or just Fo<sub>70</sub> with Fa<sub>30</sub> implied). Forsterite's melting temperature is unusually high at atmospheric pressure, almost {{convert|1900|C}}, while fayalite's is much lower –&nbsp;about {{convert|1200|C}}. Melting temperature varies smoothly between the two endmembers, as do other properties. Olivine incorporates only minor amounts of elements other than [[oxygen]] (O), [[silicon]] (Si), [[magnesium]] (Mg) and [[iron]] (Fe). [[Manganese]] (Mn) and [[nickel]] (Ni) commonly are the additional elements present in highest concentrations.

Olivine gives its name to the group of minerals with a related structure (the '''olivine group''') –&nbsp;which includes [[tephroite]] ([[manganese|Mn]]<sub>2</sub>SiO<sub>4</sub>), [[monticellite]] ([[calcium|Ca]]MgSiO<sub>4</sub>), [[larnite]] (Ca<sub>2</sub>SiO<sub>4</sub>) and [[kirschsteinite]] (CaFeSiO<sub>4</sub>) (commonly also spelled kirschteinite{{sfn|Klein|Hurlbut|1985|p=373}}).

Olivine's crystal structure incorporates aspects of the [[orthorhombic]] P [[Bravais lattice]], which arise from each silica (SiO<sub>4</sub>) unit being joined by metal divalent cations with each oxygen in SiO<sub>4</sub> bound to three metal ions. It has a [[spinel]]-like structure similar to magnetite but uses one quadrivalent and two divalent cations M<sub>2</sub><sup>2+</sup> M<sup>4+</sup>O<sub>4</sub> instead of two trivalent and one divalent cations.<ref>Ernst, W. G. ''Earth Materials''. Englewood Cliffs, NJ: Prentice-Hall, 1969. p. 65</ref>

==Identification and paragenesis==
Olivine is named for its typically olive-green color, {{cn span|date=February 2021|thought to be a result of traces of [[nickel]],}} though it may alter to a reddish color from the oxidation of iron.

Translucent olivine is sometimes used as a [[gemstone]] called [[peridot]] (''péridot'', the [[French language|French]] word for olivine). It is also called chrysolite (or ''chrysolithe'', from the [[Greek language|Greek]] words for [[gold]] and stone), though this name is now rarely used in the English language. Some of the finest gem-quality olivine has been obtained from a body of [[Mantle (geology)|mantle]] rocks on [[Zabargad Island]] in the [[Red Sea]].<ref>[http://www.mindat.org/loc-6423.html St. John's Island peridot information and history] at [[Mindat.org]]</ref><ref>{{cite journal |last1=Gubelin |first1=Edward |title=Zabargad: The ancient peridot island in the Red Sea |journal=Gems & Gemology |date=Spring 1981 |volume=17 |pages=2–8 |doi=10.5741/GEMS.17.1.2 |url=https://www.gia.edu/doc/Spring-1981-Gems-Gemology-Zabargad-Peridot-Island-Red-Sea.pdf |access-date=6 February 2021}}</ref>

Olivine occurs in both [[mafic]] and [[ultramafic]] [[igneous rock]]s and as a primary mineral in certain [[metamorphic rock]]s. Mg-rich olivine crystallizes from [[magma]] that is rich in magnesium and low in [[silica]]. That magma crystallizes to mafic rocks such as [[gabbro]] and [[basalt]].{{sfn|Klein|Hurlbut|1985|pp=374-375}} Ultramafic rocks usually contain substantial olivine, and those with an olivine content of over 40% are described as [[peridotite]]s. [[Dunite]] has an olivine content of over 90% and is likely a [[cumulate]] formed by olivine crystallizing and settling out of magma or a [[Vein (geology)|vein]] mineral lining magma conduits.<ref>{{cite book |last1=Philpotts |first1=Anthony R. |last2=Ague |first2=Jay J. |title=Principles of igneous and metamorphic petrology |date=2009 |publisher=Cambridge University Press |location=Cambridge, UK |isbn=9780521880060 |edition=2nd |pages=44, 138, 142, 385}}</ref> Olivine and high pressure structural variants constitute over 50% of the Earth's upper mantle, and olivine is one of the Earth's most common minerals by volume.<ref>{{cite journal|last1=McDonough |first1=W.F. |last2= Rudnick |first2=R.L. |year=1998 |title=Mineralogy and composition of the upper mantle |journal=Reviews in Mineralogy |volume=37 |pages=139–164 |url=https://www.researchgate.net/publication/284507003 |access-date=6 February 2021}}</ref> The [[metamorphism]] of impure [[Dolomite (rock)|dolomite]] or other [[sedimentary rock]]s with high magnesium and low silica content also produces Mg-rich olivine, or [[forsterite]].

Fe-rich olivine [[fayalite]] is relatively much less common, but it occurs in [[igneous rock]]s in small amounts in rare [[granite]]s and [[rhyolite]]s, and extremely Fe-rich olivine can exist stably with [[quartz]] and [[tridymite]]. In contrast, Mg-rich olivine does not occur stably with [[silica]] minerals, as it would react with them to form [[orthopyroxene]] ({{chem2|(Mg,Fe)2Si2O6}}).

Mg-rich olivine is stable to pressures equivalent to a depth of about {{convert|410|km|abbr=on}} within Earth. Because it is thought to be the most abundant mineral in Earth's mantle at shallower depths, the properties of olivine have a dominant influence upon the [[rheology]] of that part of Earth and hence upon the solid flow that drives [[plate tectonics]]. Experiments have documented that olivine at high pressures (12&nbsp;[[GPa]], the pressure at depths of about {{convert|360|km|abbr=on}}) can contain at least as much as about 8900 parts per million (weight) of water, and that such water content drastically reduces the resistance of olivine to solid flow. Moreover, because olivine is so abundant, more water may be dissolved in olivine of the mantle than is contained in Earth's oceans.<ref>{{cite journal|doi=10.1029/2006GL026194|title=Olivine hydration in the deep upper mantle: Effects of temperature and silica activity|year=2006|last1=Smyth|first1=J. R.|last2=Frost|first2=D. J.|last3=Nestola|first3=F.|last4=Holl|first4=C. M.|last5=Bromiley|first5=G.|journal=Geophysical Research Letters|volume=33|issue=15|pages=L15301|bibcode=2006GeoRL..3315301S|hdl=11577/1563853 |url=http://ruby.colorado.edu/~smyth/Research/Papers/Hydrolivine.pdf|url-status=dead|archive-url=https://web.archive.org/web/20170809105549/http://ruby.colorado.edu/%7Esmyth/Research/Papers/Hydrolivine.pdf|archive-date=2017-08-09|citeseerx=10.1.1.573.4309|s2cid=35342757 |access-date=2017-10-26}}</ref>

Olivine pine forest (a [[plant community]]) is unique to Norway. It is rare and found on dry olivine ridges in the fjord districts of Sunnmøre and Nordfjord.<ref>{{cite journal |last1=Brandrud |first1=T.E. |year=2009 |title=Olivinfuruskog og rødlistearter i Bjørkedalen, Volda: naturverdi og forvaltningsmuligheter |journal=NINA Rapport |volume=461 |url=https://brage.nina.no/nina-xmlui/handle/11250/2397756 |access-date=14 February 2021 |language=norwegian}}</ref>

<gallery widths="180px" heights="150px">
File:Papakolea Beach sand high mag 052915.jpg|Olivine grains that eroded from [[lava]] on [[Papakolea Beach]], [[Hawaii]]
File:Peridot in basalt.jpg|Light green olivine crystals in peridotite xenoliths in basalt from Arizona
File:Lunar Olivine Basalt 15555 from Apollo 15 in National Museum of Natural History.jpg|Olivine [[basalt]] from the Moon, collected in 1971 by the crew of [[Apollo 15]]
File:Forsterite-158776.jpg|Bright green olivine from Pakistan, showing chisel termination and silky luster
File:Lava - Olivine - Azores.jpg|Olivine in lava from the [[Azores]]
</gallery>

===Extraterrestrial occurrences===
[[File:Météorite Esquel, exposition Météorites, Muséum national d'histoire naturelle de Paris 05.jpg|thumb|right|Crystals of olivine embedded in iron, in a slice of [[Esquel (meteorite)|Esquel]], a [[pallasite]] [[meteorite]]]]

Mg-rich olivine has also been discovered in [[meteorite]]s,<ref>[http://www.farlang.com/art/gemstone-meteorites Fukang and other Pallasites] {{webarchive|url=https://web.archive.org/web/20081221151620/http://www.farlang.com/art/gemstone-meteorites |date=2008-12-21}}. Farlang.com (2008-04-30). Retrieved on 2012-06-16.</ref> on the [[Moon]]<ref name="MareBasalt1">{{cite web | url=https://curator.jsc.nasa.gov/lunar/letss/mare3.pdf | title=Mare Basalt Volcanism | publisher=[[NASA]] | work=NASA Lunar Petrographic Educational Thin Section Set | date=2003 | access-date=23 October 2016 | author=Meyer, C. | url-status=live | archive-url=https://web.archive.org/web/20161221110429/https://curator.jsc.nasa.gov/lunar/letss/mare3.pdf | archive-date=21 December 2016}}</ref> and [[Mars]],<ref>[http://www.psrd.hawaii.edu/Nov03/olivine.html Pretty Green Mineral....] {{webarchive|url=https://web.archive.org/web/20070504025123/http://www.psrd.hawaii.edu/Nov03/olivine.html |date=2007-05-04}}[http://deepimpact.umd.edu/gallery/313_635_F3.html Mission Update 2006...] {{webarchive|url=https://web.archive.org/web/20100605183617/http://deepimpact.umd.edu/gallery/313_635_F3.html |date=2010-06-05}} UMD Deep Impact Website, University of Maryland Ball Aerospace & Technology Corp. retrieved June 1, 2010</ref><ref>Hoefen, T.M., et al. 2003. "Discovery of Olivine in the Nili Fossae Region of Mars". ''Science'' 302, 627–30. "{{cite journal |title=Discovery of Olivine in the Nili Fossae Region of Mars |journal=Science |volume=302 |issue=5645 |pages=627–630 |doi=10.1126/science.1089647 |year=2003 |last1=Hoefen |first1=T. M. |url=https://zenodo.org/record/1230836 |bibcode=2003Sci...302..627H |pmid=14576430|s2cid=20122017 }}"</ref> falling into infant stars,<ref>[http://www.nasa.gov/mission_pages/spitzer/news/spitzer20110526.html Spitzer Sees Crystal Rain...] {{webarchive|url=https://web.archive.org/web/20110529000009/http://www.nasa.gov/mission_pages/spitzer/news/spitzer20110526.html |date=2011-05-29}} NASA Website</ref> as well as on asteroid [[25143 Itokawa]].<ref>[http://www.spaceflightnow.com/news/n1011/16hayabusa/ Japan says Hayabusa brought back asteroid grains...] {{webarchive|url=https://web.archive.org/web/20101118234721/http://www.spaceflightnow.com/news/n1011/16hayabusa/ |date=2010-11-18}} retrieved November 18, 2010</ref> Such meteorites include [[chondrite]]s, collections of debris from the early [[Solar System]]; and [[pallasite]]s, mixes of iron-nickel and olivine. The rare [[A-type asteroid]]s are suspected to have a surface dominated by olivine.<ref>{{cite journal | title=Olivine-dominated asteroids: Mineralogy and origin | last1=Sanchez | first1=Juan A. | last2=Reddy | first2=Vishnu | last3=Kelley | first3=Michael S. | last4=Cloutis | first4=Edward A. | last5=Bottke | first5=William F. | last6=Nesvorný | first6=David | last7=Lucas | first7=Michael P. | last8=Hardersen | first8=Paul S. | last9=Gaffey | first9=Michael J. | last10=Abell | first10=Paul A. | last11=Le Corre | first11=Lucille | display-authors=1 | journal=Icarus | volume=228 | pages=288–300 | date=January 2014 | doi=10.1016/j.icarus.2013.10.006 | arxiv=1310.1080 | bibcode=2014Icar..228..288S | s2cid=42791787 }}</ref>

The [[spectral signature]] of olivine has been seen in the dust disks around young stars. The tails of comets (which formed from the dust disk around the young [[Sun]]) often have the spectral signature of olivine, and the presence of olivine was verified in samples of a comet from the [[Stardust (spacecraft)#Sample analysis|Stardust spacecraft]]{{Broken anchor|date=2024-06-25|bot=User:Cewbot/log/20201008/configuration|target_link=Stardust (spacecraft)#Sample analysis|reason= The anchor (Sample analysis) [[Special:Diff/413803820|has been deleted]].}} in 2006.<ref>[http://stardust.jpl.nasa.gov/news/status/060313.html Press Release 06-091] {{webarchive|url=https://web.archive.org/web/20060828230900/http://stardust.jpl.nasa.gov/news/status/060313.html |date=2006-08-28}}. Jet Propulsion Laboratory Stardust website, retrieved May 30, 2006.</ref> Comet-like (magnesium-rich) olivine has also been detected in the [[planetesimal]] belt around the star [[Beta Pictoris]].<ref name="deVries2012">{{Cite journal | last1=De Vries | first1=B. L. | last2=Acke | first2=B. | last3=Blommaert | first3=J. A. D. L. | last4=Waelkens | first4=C. | last5=Waters | first5=L. B. F. M. | last6=Vandenbussche | first6=B. | last7=Min | first7=M. | last8=Olofsson | first8=G. | last9=Dominik | first9=C. | last10=Decin | doi=10.1038/nature11469 | first10=L. | last11=Barlow | first11=M. J. | last12=Brandeker | first12=A. | last13=Di Francesco | first13=J. | last14=Glauser | first14=A. M. | last15=Greaves | first15=J. | last16=Harvey | first16=P. M. | last17=Holland | first17=W. S. | last18=Ivison | first18=R. J. | last19=Liseau | first19=R. | last20=Pantin | first20=E. E. | last21=Pilbratt | first21=G. L. | last22=Royer | first22=P. | last23=Sibthorpe | first23=B. | title=Comet-like mineralogy of olivine crystals in an extrasolar proto-Kuiper belt | journal=Nature | volume=490 | issue=7418 | pages=74–76 | year=2012 | pmid=23038467 | arxiv=1211.2626 | bibcode=2012Natur.490...74D| s2cid=205230613 }}</ref>

==Crystal structure==
[[File:Atomic structure of olivine 1.png|left|thumb|The atomic scale structure of olivine looking along the ''a'' axis. Oxygen is shown in red, silicon in pink, and magnesium/iron in blue. A projection of the unit cell is shown by the black rectangle.]]
Minerals in the olivine group crystallize in the [[orthorhombic]] system ([[space group]] P''bnm'') with isolated silicate tetrahedra, meaning that olivine is a [[Silicate minerals|nesosilicate]]. The structure can be described as a hexagonal, close-packed array of oxygen [[ion]]s with half of the octahedral sites occupied with magnesium or iron ions and one-eighth of the tetrahedral sites occupied by silicon ions.

There are three distinct oxygen sites (marked O1, O2 and O3 in the figure), two distinct metal sites (M1 and M2) and only one distinct silicon site. O1, O2, M2 and Si all lie on [[mirror plane]]s, while M1 exists on an inversion center. O3 lies in a general position.

==High-pressure polymorphs==
At the high temperatures and pressures found at depth within the Earth the olivine structure is no longer stable. Below depths of about {{convert|410|km|abbr=on}} olivine undergoes an exothermic [[phase transition]] to the [[silicate minerals|sorosilicate]], [[wadsleyite]] and, at about {{convert|520|km|abbr=on}} depth, wadsleyite transforms exothermically into [[ringwoodite]], which has the [[spinel]] structure. At a depth of about {{convert|660|km|abbr=on}}, ringwoodite decomposes into [[silicate perovskite]] ({{chem2|(Mg,Fe)SiO3}}) and [[ferropericlase]] ({{chem2|(Mg,Fe)O}}) in an endothermic reaction. These phase transitions lead to a discontinuous increase in the density of the Earth's [[mantle (geology)|mantle]] that can be observed by [[seismic]] methods. They are also thought to influence the dynamics of [[mantle convection]] in that the exothermic transitions reinforce flow across the phase boundary, whereas the endothermic reaction hampers it.<ref>{{cite journal|last=Christensen|first=U.R.|title=Effects of phase transitions on mantle convection|journal=Annu. Rev. Earth Planet. Sci.|year=1995|volume=23|pages=65–87|doi=10.1146/annurev.ea.23.050195.000433|bibcode = 1995AREPS..23...65C}}</ref>

The pressure at which these phase transitions occur depends on temperature and iron content.<ref>{{cite book
 |last = Deer
 |first = W. A.
 |author2=R. A. Howie |author3=J. Zussman
 |title = An Introduction to the Rock-Forming Minerals |edition=2nd
 |publisher = Longman
 |year = 1992
 |location = London
 |isbn =  978-0-582-30094-1}}</ref> At {{convert|800|C|K F}}, the pure magnesium end member, forsterite, transforms to wadsleyite at {{convert|11.8|GPa|atm|lk=on}} and to ringwoodite at pressures above {{convert|14|GPa|atm|abbr=on|sigfig=3}}. Increasing the iron content decreases the pressure of the phase transition and narrows the [[wadsleyite]] stability field. At about 0.8 [[mole fraction]] fayalite, olivine transforms directly to ringwoodite over the pressure range {{convert|10.0|to(-)|11.5|GPa|atm|abbr=on}}. Fayalite transforms to {{chem|Fe|2|SiO|4}} spinel at pressures below {{convert|5|GPa|atm|abbr=on}}. Increasing the temperature increases the pressure of these phase transitions.

==Weathering==
[[File:Iddingsite.JPG|thumb|Olivine altered to iddingsite within a [[Mantle (geology)|mantle]] [[xenolith]].]]

Olivine is one of the less stable common minerals on the surface according to the [[Goldich dissolution series]]. It alters into [[iddingsite]] (a combination of clay minerals, iron oxides and [[ferrihydrite]]) readily in the presence of water.<ref>{{cite journal | author1 = Kuebler, K. | author2 = Wang, A. | author3 = Haskin, L. A. | author4 = Jolliff, B. L. | url = http://www.lpi.usra.edu/meetings/lpsc2003/pdf/1953.pdf | title = A Study of Olivine Alteration to Iddingsite Using Raman Spectroscopy | journal = Lunar and Planetary Science | year = 2003 | volume = 34 | page = 1953 | url-status = live | archive-url = https://web.archive.org/web/20121025024139/http://www.lpi.usra.edu/meetings/lpsc2003/pdf/1953.pdf | archive-date = 2012-10-25 | bibcode = 2003LPI....34.1953K}}</ref> Artificially increasing the weathering rate of olivine, e.g. by dispersing fine-grained olivine on beaches, has been proposed as a cheap way to sequester CO<sub>2</sub>.<ref>{{cite web |author1= Goldberg, Philip |author2= Chen Zhong-Yin |author3= Connor, William'O |author4= Walters, Richards |author5= Ziock, Hans |title= CO2 Mineral Sequestration Studies in US |date= 2001 |url= https://www.netl.doe.gov/publications/proceedings/01/carbon_seq/6c1.pdf |url-status= dead |archive-url= https://web.archive.org/web/20161221131438/http://www.netl.doe.gov/publications/proceedings/01/carbon_seq/6c1.pdf |archive-date= 2016-12-21 |access-date= 2016-12-19}}</ref><ref>{{cite web|author1=Schuiling, R.D.|author2=Tickell, O.|title=Olivine against climate change and ocean acidification|url=http://www.innovationconcepts.eu/res/literatuurSchuiling/olivineagainstclimatechange23.pdf|url-status=dead|archive-url=https://web.archive.org/web/20160927013859/http://www.innovationconcepts.eu/res/literatuurSchuiling/olivineagainstclimatechange23.pdf|archive-date=2016-09-27|access-date=2016-12-19}}</ref> The presence of iddingsite on Mars would suggest that liquid water once existed there, and might enable scientists to determine when there was last liquid water on the planet.<ref>{{cite journal | last1=Swindle | first1=T. D. | last2=Treiman | first2=A. H. | last3=Lindstrom | first3=D. J. | last4=Burkland | first4=M. K. | last5=Cohen | first5=B. A. | last6=Grier | first6=J. A.|author6-link=JA Grier | last7=Li | first7=B. | last8=Olson | first8=E. K. | title=Noble Gases in Iddingsite from the Lafayette meteorite: Evidence for Liquid water on Mars in the last few hundred million years | journal=Meteoritics and Planetary Science | year=2000 | volume=35 | issue=1 | pages=107–15 | doi=10.1111/j.1945-5100.2000.tb01978.x | bibcode=2000M&PS...35..107S| doi-access=free }}</ref>

Because of its rapid weathering, olivine is rarely found in [[sedimentary rock]].<ref>{{cite journal |last1=Velbel |first1=Michael A. |title=Dissolution of olivine during natural weathering |journal=Geochimica et Cosmochimica Acta |date=October 2009 |volume=73 |issue=20 |pages=6098–6113 |doi=10.1016/j.gca.2009.07.024|bibcode=2009GeCoA..73.6098V }}</ref>

==Mining==
===Norway===
[[File:Sunnylvsfjord MS-Midnatsol.jpg|thumb|Open-pit mining at [[Sunnylvsfjorden]], [[Hurtigruten]] ship passing.]]

Norway is the main source of olivine in Europe, particularly in an area stretching from [[Åheim]] to [[Tafjord]], and from [[Hornindal Municipality|Hornindal]] to Flemsøy in the [[Sunnmøre]] district. There is also olivine in [[Stad Municipality]]. About 50% of the world's olivine for industrial use is produced in Norway. At Svarthammaren in [[Norddal Municipality]] (now [[Fjord Municipality]]), olivine was mined from around 1920 to 1979, with a daily output up to {{convert|600|MT|lk=on}}. Olivine was also obtained from the construction site of the hydro power stations in Tafjord. At Robbervika in Norddal municipality an open-pit mine has been in operation since 1984. The characteristic red color is reflected in several local names with "red" such as ''Raudbergvik'' (Red rock bay) or ''Raudnakken'' (Red ridge).<ref>Furseth, Astor (1987): ''Norddal i 150 år''. Valldal: Norddal kommune.</ref><ref>[[Geological Survey of Norway]]. ''[https://geo.ngu.no/kart/mineralressurser/ Kart over mineralressurser] {{webarchive|url=https://web.archive.org/web/20171014020956/http://geo.ngu.no/kart/mineralressurser/ |date=2017-10-14}}''. Accessed 9.12.2012.</ref><ref>{{Cite web|url=http://www.ngu.no/fagomrade/olivin|title=Olivin|website=www.ngu.no|language=nb|access-date=2017-11-09|url-status=dead|archive-url=https://web.archive.org/web/20171110115920/http://www.ngu.no/fagomrade/olivin|archive-date=2017-11-10}}</ref><ref>Gjelsvik, T. (1951). ''[http://www.ngu.no/FileArchive/NGUPublikasjoner/NGUnr_179_Gjelsvik.pdf Oversikt over bergartene i Sunnmøre og tilgrensende deler av Nordfjord] {{webarchive|url=https://web.archive.org/web/20171110005426/http://www.ngu.no/FileArchive/NGUPublikasjoner/NGUnr_179_Gjelsvik.pdf |date=2017-11-10}}''. Norge geologiske undersøkelser, report 179.</ref>

[[Hans Strøm]] in 1766 described the olivine's typical red color on the surface and the blue color within. Strøm wrote that in Norddal district large quantities of olivine were broken from the bedrock and used as [[sharpening stone]]s.<ref>Strøm, Hans: ''Physisk og Oeconomisk Beskrivelse over Fogderiet Søndmør beliggende i Bergen Stift i Norge.'' Published in Sorø, Denmark, 1766.</ref>

Kallskaret near Tafjord is a nature reserve with olivine.<ref>{{cite web|url=http://snl.no/Kallskaret|title=Kallskaret|date=28 September 2014|access-date=3 May 2018|via=Store norske leksikon|url-status=live|archive-url=https://web.archive.org/web/20171110114348/https://snl.no/Kallskaret|archive-date=10 November 2017}}</ref>

==Applications==
Olivine is used as a substitute for [[Dolomite (mineral)|dolomite]] in steel works.<ref>''Mineralressurser i Norge ; Mineralstatistikk og bergverksberetning 2006.'' Trondheim: Bergvesenet med bergmesteren for Svalbard. 2007.</ref>

The aluminium foundry industry uses olivine sand to cast objects in aluminium. Olivine sand requires less water than silica sands while still holding the mold together during handling and pouring of the metal. Less water means less gas (steam) to vent from the mold as metal is poured into the mold.<ref>{{cite book | last = Ammen | first = C. W. | title = The Metal Caster's Bible | publisher = TAB | year = 1980 | location = Blue Ridge Summit PA | page = [https://archive.org/details/metalcastersbibl00amme/page/331 331] | isbn = 978-0-8306-9970-4 | url = https://archive.org/details/metalcastersbibl00amme/page/331}}</ref>

In Finland, olivine is marketed as an ideal rock for [[sauna]] stoves because of its comparatively high density and resistance to weathering under repeated heating and cooling.<ref>{{cite web |title=The olivine stone |url=https://suomenkiuaskivi.fi/en/the-olivine-stone/ |website=Suomen Kiuaskivi |access-date=14 February 2021 |archive-date=5 March 2021 |archive-url=https://web.archive.org/web/20210305102844/https://suomenkiuaskivi.fi/en/the-olivine-stone/ |url-status=dead }}</ref>

Gem-quality olivine is used as a [[gemstone]] called [[peridot]].
==Experimental uses==
Removal of atmospheric CO<sub>2</sub> via reaction with crushed olivine has been considered. The end-products of the very slow reaction are [[silicon dioxide]], [[magnesium carbonate]], and iron oxides.<ref>{{cite journal | author1=Goldberg, P. | author2=Chen, Z.-Y. | author3=O'Connor, W. | author4=Walters, R. | author5=Ziock, H. | url=http://www.netl.doe.gov/publications/proceedings/01/carbon_seq/6c1.pdf | title=CO<sub>2</sub> Mineral Sequestration Studies in US | journal=Technology | year=2000 | volume=1 | issue=1 | pages=1–10 | url-status=dead | archive-url=https://web.archive.org/web/20031207120418/http://www.netl.doe.gov/publications/proceedings/01/carbon_seq/6c1.pdf | archive-date=2003-12-07 | access-date=2008-07-07}}</ref><ref>{{cite journal | title=Enhanced Weathering: An Effective and Cheap Tool to Sequester CO<sub>2</sub> | year=2006 | last1=Schuiling | first1=R. D. | last2=Krijgsman | first2=P. | journal=Climatic Change | volume=74 | issue=1–3 | pages=349–54 | doi=10.1007/s10584-005-3485-y| bibcode=2006ClCh...74..349S | s2cid=131280491 }}</ref> A public benefit corporation, [[Project Vesta]], is investigating this approach on beaches which increase the agitation and surface area of crushed olivine through wave action.<ref>{{Cite web|last=Delbert|first=Caroline|date=2020-06-11|title=How This Strange Green Sand Could Reverse Climate Change|url=https://www.popularmechanics.com/science/environment/a32799266/green-sand-carbon-dioxide-climate-change/|access-date=2020-11-06|website=Popular Mechanics|language=en-US}}</ref>

==See also==
{{Portal|Minerals}}
* {{annotated link|Bowen's reaction series}}
* {{annotated link|List of minerals}}

==References==
{{Reflist}}

==External links==
{{Commons category|Olivine}}
* [http://www.psrd.hawaii.edu/Nov03/olivine.html Pretty Green Mineral – Pretty Dry Mars?] by Linda M.V. Martel, Planetary Science Research Discoveries, Hawai'i Institute of Geophysics and Planetology
* [https://web.archive.org/web/20081223053155/http://www.farlang.com/gemstones/peridot Olivine Page] Farlang library: Historic sources + modern articles on Olivine and Peridot
* [http://www.und.nodak.edu/instruct/mineral/320petrology/opticalmin/olivine.htm Geological information and several microscopic images] University of North Dakota

{{Minerals}}
{{Authority control}}

[[Category:Industrial minerals]]
[[Category:Iron(II) minerals]]
[[Category:Magnesium minerals]]
[[Category:Minerals in space group 62]]
[[Category:Nesosilicates]]
[[Category:Orthorhombic minerals]]

[[de:Olivingruppe]]