{{Short description|Sorosilicate mineral}} {{Infobox mineral | name = Normandite | boxwidth = | boxbgcolor = | image = Normandite.jpg | imagesize = | alt = | caption = | struct image = | struct caption = | struct imagesize = | struct2 image = | struct2 caption = | struct2 imagesize= | SMILES = | Jmol = | category = | formula = {{chem2|NaCa(Mn(2+),Fe(2+))(Ti,Nb,Zr)Si2O7(O,F)2}} | IMAsymbol = Nmd<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> | molweight = | strunz = | dana = | system = Monoclinic | class = | symmetry = ''P2<sub>1</sub>/a'' (no. 14) | unit cell = | color = | colour = | habit = | twinning = | cleavage = | fracture = | tenacity = | toughness = | mohs = 5 - 6 | luster = | streak = | diaphaneity = | gravity = 3.48 - 3.5 | density = | polish = | opticalprop = | refractive = | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | Curie temp = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = <ref>{{cite journal |last1=Perchiazzi |first1=N. |last2=McDonald |first2=A. M. |last3=Gault |first3=R. A. |last4=Johnsen |first4=O. |last5=Merlino |first5=S. |title=The Crystal Structure of Normandite and Its Crystal-Chemical Relationships With Lavenite |journal=The Canadian Mineralogist |date=1 June 2000 |volume=38 |issue=3 |pages=641–648 |doi=10.2113/gscanmin.38.3.641|bibcode=2000CaMin..38..641P |citeseerx=10.1.1.577.3937 }}</ref> | var1 = | var1text = | var2 = | var2text = | var3 = | var3text = | var4 = | var4text = | var5 = | var5text = | var6 = | var6text = }} '''Normandite''' is a brittle orange brown sorosilicate mineral discovered in 1997 by Charles Normand (born 1963), of Montreal. Normandite occurs in Khibiny Massif, Kola, Russia; in Poudrette quarry, Mont-Saint-Hilaire, Quebec (type locality) and Tenerife, Canary Islands. It is found in nepheline syenite and in miarolitic cavities in nepheline syenite, associated with nepheline, albite, microcline, aegirine, natrolite, catapleiite, kupletskite, eudialyte, cancrinite, villiaumite, rinkite, and donnayite-(Y).
Normandite has a chemical formula of {{chem2|NaCa(Mn(2+),Fe(2+))(Ti,Nb,Zr)Si2O7(O,F)2}}. It crystallizes in the monoclinic-prismatic crystal system. It occurs as transparent to translucent orange-brown aggregates of subparallel acicular crystals up to 10 mm in length, and as patches of yellow, fibrous crystals. It has a white to very pale yellow streak and vitreous luster. It is brittle, with distinct {100} and {001} cleavages, and a conchoidal fracture. It has a specific gravity of 3.48 to 3.5, a Mohs hardness of 5 to 6 and refractive index values of nα=1.743, nβ=1.785 and nγ=1.810. It is named after Charles Normand (born 1963), Canadian geologist.
==References== {{reflist}}
*[http://webmineral.com/data/Normandite.shtml Webmineral data] *[http://www.mindat.org/show.php?id=2932 Mindat with location data] *[http://www.saint-hilaire.ca/en/normand.htm Saint-Hilaire] *[http://www.saint-hilaire.ca/abs/CM351035.htm The Canadian Mineralogist 1999 abstract]
Category:Sorosilicates Category:Monoclinic minerals Category:Minerals in space group 14