{{Short description|Phosphate mineral}} {{Distinguish|Lazurite|Lapis lazuli}} {{Other uses|Azure spar}} {{Infobox mineral | name = Lazulite | boxwidth = | boxbgcolor = | image = Lazulite-tmix07-168a.jpg | imagesize = | alt = | caption = Lazulite specimen found near Rapid Creek, Yukon, Canada | category = Phosphate mineral | formula = {{chem2|(Mg,Fe(2+))Al2(PO4)2(OH)2}} | IMAsymbol = Lzl<ref>{{Cite journal |last=Warr|first=L. N. |year=2021 |title=IMA–CNMNC approved mineral symbols |journal=Mineralogical Magazine |volume=85 |issue=3 |pages=291–320 |publisher=Mineralogical Society of Great Britain and Ireland |doi=10.1180/mgm.2021.43 |bibcode=2021MinM...85..291W |s2cid=235729616 |doi-access=free}}</ref> | molweight = | strunz = 8.BB.40 | dana = | system = Monoclinic | class = Prismatic (2/m) <br/><small>(same H–M symbol)</small> | symmetry = ''P2''<sub>1</sub>/c | unit cell = a = 7.144(1), b = 7.278(1) <br/>c = 7.228(1)&nbsp;[Å]; β = 120.5(1)°; Z&nbsp;=&nbsp;2 | color = Azure, sky blue, bluish white, yellow-green, blue-green, rarely green | habit = Tabular, acute to stubby bipyramidal crystals; granular, massive | twinning = Common by several twin laws | cleavage = Poor to good on {110}, indistinct on {101} | fracture = Uneven, splintery | tenacity = Brittle | mohs = 5.5–6.0 | luster = Vitreous | streak = White | diaphaneity = Transparent to translucent to nearly opaque | gravity = 3.122–3.240 | opticalprop = Biaxial (−) | refractive = n<sub>α</sub> = 1.604–1.626<br>n<sub>β</sub> = 1.626–1.654<br>n<sub>γ</sub> = 1.637–1.663 | birefringence = δ = 0.033–0.037 | pleochroism = Strong: X = colorless, Y = blue, Z = darker blue | 2V = Measured: 61–70° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = Infusible | diagnostic = | solubility = Insoluble | impurities = | alteration = | other = | references = <ref name=HBM/><ref name=Mindat/><ref name=Webmin>{{WebMineral |url=https://webmineral.com/data/Lazulite.shtml |title=Lazulite Mineral Data}}</ref><ref name=Manual/> }}

'''Lazulite''' or ''Azure spar''<ref name="kriv">''Krivovichev V. G.'' Mineralogical glossary. Scientific editor A. G. Bulakh. — St.Petersburg: St.Petersburg Univ. Publ. House. 2009. — 556 p. ''(in Russian)''</ref>{{rp|14}} is a transparent to semi-opaque, blue mineral that is a phosphate of magnesium, iron, and aluminium, with the chemical formula {{chem2|(Mg,Fe(2+))Al2(PO4)2(OH)2}}.<ref name=Mindat>{{Mindat |id=2356 |name=Lazulite}}</ref> Lazulite forms one endmember of a solid solution series with the darker, iron-rich scorzalite.<ref name=Mindat/><ref name=Manual/>

Lazulite crystallizes in the monoclinic system. Its crystal habits include steep bipyramidal or wedge-shaped crystals.<ref>{{cite web |url=https://minerals.net/mineral/lazulite.aspx |title=Lazulite |publisher=Minerals.net}}</ref> Lazulite has a Mohs hardness of 5.5–6.0 and a specific gravity of 3.0–3.1. It is infusible and insoluble.<ref name=Manual>{{cite book |last1=Hurlbut|first1=Cornelius S. |last2=Klein|first2=Cornelius |year=1985 |title=Manual of Mineralogy |edition=20th |publisher=Wiley |ISBN=0-471-80580-7}}</ref>

==Occurrence and discovery== [[File:Lazulite-dtn2a.jpg|thumb|left| upright|Lazulite from Laila,(Village Dasso) Kutwal Valley Haramosh Gilgit District, Gilgit-Baltistan, Pakistan. Size: {{cvt|2.4|×|1.7|×|0.8|cm|in}}.]]

Lazulite forms by high-grade metamorphism of silica-rich rocks and in pegmatites. It occurs in association with quartz, andalusite, rutile, kyanite, corundum, muscovite, pyrophyllite, dumortierite, wagnerite, svanbergite, trolleite, and berlinite in metamorphic terrains; and with albite, quartz, muscovite, tourmaline and beryl in pegmatites.<ref name=HBM/> It may be confused with lazurite, lapis lazuli or azurite.

The type locality is in Freßnitzgraben in Krieglach, it's also found in Salzburg, Austria; Zermatt, Switzerland; Minas Gerais, Brazil; Lincoln County, Georgia; Inyo County, California; the Yukon in Canada; and elsewhere.

It was first described in 1795 for deposits in Styria, Austria.<ref name=Mindat/> Its name comes from the German {{lang|de|lazurstein}}, for 'blue stone'<ref name=HBM>{{cite web |url=http://rruff.geo.arizona.edu/doclib/hom/lazulite.pdf |work=Handbook of Mineralogy |title=Lazulite |publisher=RRUFF |url-status=live |archive-url=https://web.archive.org/web/20210705152731/https://rruff.info/doclib/hom/lazulite.pdf |archive-date= Jul 5, 2021 }}</ref> or from the Arabic for heaven.<ref name=Mindat/><ref name=Manual/> {{clear|left}}

==References== {{Commons category|Lazulite|position=left}} {{Reflist}}

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Category:Aluminium minerals Category:Iron(II) minerals Category:Magnesium minerals Category:Phosphate minerals Category:Monoclinic minerals Category:Minerals in space group 14