Editing Samarskite-(Y)

{{Short description|Rare earth oxide mineral}}
{{Infobox mineral
| name        = '''Samarskite-(Y)'''
| category    = [[Oxide minerals]]
| boxwidth    = 
| boxbgcolor  =#6a6750 
| boxtextcolor = #fff
| image       = Samarskite-(Y)-351417.jpg
| imagesize   = 
| caption     = 
| formula     = {{chem2|(YFe(3+)Fe(2+)U,Th,Ca)2(Nb,Ta)2O8}}
| IMAsymbol   = Smk-Y<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      = 4.DB.25
| system      = [[Orthorhombic]]
| class       = Dipyramidal (mmm) <br/>[[H-M symbol]]: (2/m 2/m 2/m)
| symmetry    = ''Pbcn''
| unit cell   = a = 5.687&nbsp;[[Ångström|Å]], b = 4.925&nbsp;Å <br/>c = 5.21&nbsp;Å; Z&nbsp;=&nbsp;2
| color       = Black, may have a brownish tint, brown to yellowish brown due to alteration; light to dark brown in transmitted light
| habit       = Crystals elongated with pyramidal terminations; commonly granular to massive
| twinning    = 
| cleavage    = {010}, indistinct 
| fracture    = Conchoidal fragments
| tenacity    = Brittle
| mohs        = 5–6
| luster      = Vitreous – resinous
| refractive  = n = 2.1–2.2
| opticalprop = Appears isotropic
| birefringence = 
| pleochroism = 
| streak      = Reddish brown
| gravity     =  
| density     = 5.6 – 5.8, Average = 5.69
| melt        = 
| fusibility  = 
| diagnostic  = 
| solubility  = 
| diaphaneity = Opaque, transparent in thin fragments
| other       = [[Image:Radioactive.svg|25px]] [[Radioactive]] (Greater than 70 Bq / gram)
| alteration  = Metamict
| references  = <ref>https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Samarskite-%28Y%29 {{Webarchive|url=https://web.archive.org/web/20190811213105/https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Samarskite-(Y) |date=2019-08-11 }} Mineralienatlas</ref><ref name=MindatY/><ref name=webmin>http://webmineral.com/data/Samarskite-(Y).shtml {{Webarchive|url=https://web.archive.org/web/20110514152137/http://www.webmineral.com/data/Samarskite-(Y).shtml |date=2011-05-14 }} Webminerals</ref><ref name=HBM/>
}}

'''Samarskite''' is a [[radioactive]] [[rare earth mineral]] series which includes '''samarskite-(Y)''', with the chemical formula {{chem2|([[Yttrium|Y]]Fe(3+)Fe(2+)U,Th,Ca)2(Nb,Ta)2O8}}<ref name=MindatY>{{Cite web |url=http://www.mindat.org/min-3512.html |title=Mindat Samarskite-(Y) |access-date=2006-08-20 |archive-date=2006-09-08 |archive-url=https://web.archive.org/web/20060908152225/http://www.mindat.org/min-3512.html |url-status=live }}</ref> and '''samarskite-(Yb)''', with the chemical formula {{chem2|([[Ytterbium|Yb]]Fe(3+))2(Nb,Ta)2O8}}.<ref name=Yb>{{Cite web |url=http://www.mindat.org/min-27449.html |title=Mindat Samarskite-(Yb) |access-date=2011-02-22 |archive-date=2010-12-23 |archive-url=https://web.archive.org/web/20101223140339/http://www.mindat.org/min-27449.html |url-status=live }}</ref> The formula for samarskite-(Y) is also given as {{chem2|(Y,Fe(3+),U)(Nb,Ta)O4}}.<ref name=HBM>{{Cite web |url=http://rruff.geo.arizona.edu/doclib/hom/samarskitey.pdf |title=Handbook of Mineralogy |access-date=2006-08-20 |archive-date=2006-09-12 |archive-url=https://web.archive.org/web/20060912221609/http://rruff.geo.arizona.edu/doclib/hom/samarskitey.pdf |url-status=live }}</ref>

Samarskite crystallizes in the orthorhombic – dipyramidal class as black to yellowish brown stubby prisms although it is typically found as [[Anhedral (petrology)|anhedral]] masses. Specimens with a high uranium content are typically [[metamict]] and appear coated with a yellow brown earthy rind. 

Samarskite occurs in rare earth bearing [[granite]] [[pegmatite]]s with other rare minerals. It occurs in association with [[columbite]], [[zircon]], [[monazite]], [[uraninite]], [[Aeschynite-(Y)|aeschynite]], [[magnetite]], [[albite]], [[topaz]], [[beryl]], [[garnet]], [[muscovite]] and [[biotite]].<ref name=HBM/>

Samarskite was first described in 1847 for an occurrence in [[Miass]], Ilmen Mountains, Southern [[Ural Mountains]] of [[Russia]].<ref name=webmin/> The chemical element [[samarium]] was first isolated from a specimen of samarskite in 1879. Samarium was named after samarskite which was named for the Russian mine official, Colonel [[Vasili Samarsky-Bykhovets]] (1803–1870).<ref name=webmin/>

Samarskite-(Yb) was first described in 2004 for an occurrence in the South Platte Pegmatite District, [[Jefferson County, Colorado]].<ref name=Yb/><ref name=WebminYb>{{Cite web |url=http://webmineral.com/data/Samarskite-(Yb).shtml |title=Samarskite-(Yb) on Webmineral |access-date=2011-02-22 |archive-date=2011-06-29 |archive-url=https://web.archive.org/web/20110629135840/http://webmineral.com/data/Samarskite-(Yb).shtml |url-status=live }}</ref>
[[Image:Samarskite-fresh.jpg|thumb|left|Samarskite specimen, broken to show fresh surface]]

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==See also==
* [[Decipium]], a [[list of misidentified chemical elements|mis-identified new element]], thought to have been extracted from samarskite in 1878 by [[Marc Delafontaine]].
*[[List of minerals]]
*[[List of minerals named after people]]

==References==
{{Commons category|Samarskite-(Y)}}
{{reflist}}

[[Category:Uranium(III) minerals]]
[[Category:Yttrium minerals]]
[[Category:Lanthanide minerals]]
[[Category:Iron(II,III) minerals]]
[[Category:Niobium minerals]]
[[Category:Tantalum minerals]]
[[Category:Oxide minerals]]
[[Category:Orthorhombic minerals]]
[[Category:Minerals in space group 60]]
[[Category:Thorium minerals]]