{{Short description|Uncommon evaporite mineral}} {{Infobox mineral | name = Northupite | boxwidth = | boxbgcolor = | image = Northupite.jpg | imagesize = 260px | alt = | caption = Northupite octahedra | category = Carbonate minerals | formula = Na<sub>3</sub>Mg(CO<sub>3</sub>)<sub>2</sub>Cl | IMAsymbol = Nup<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 = 5.BF.05 | dana = | system = Isometric | class = Diploidal (m{{overline|3}}) <br/>H-M symbol: (2/m{{overline|3}}) | symmetry = ''F''d3 | unit cell = a = 13.98&nbsp;Å; Z&nbsp;=&nbsp;16 | colour = Colourless, pale yellow, grey, brown; colourless in transmitted light | habit = Octahedral crystals; globular, massive | twinning = | cleavage = | fracture = Conchoidal | tenacity = Brittle | mohs = {{frac|3|1|2}} – 4 | lustre = Vitreous | streak = | diaphaneity = Transparent | gravity = 2.380–2.407 | density = | polish = | opticalprop = Isotropic | refractive = n = 1.5144 (to 1.550 with iron substitution) | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = Readily soluble in dilute acids with effervescence. Decomposed by hot water with the separation of magnesium carbonate. | impurities = | alteration = | other = | prop1 = | prop1text = | references = <ref name=HBM>[http://rruff.info/doclib/hom/northupite.pdf Handbook of Mineralogy]</ref><ref name=Mindat>[http://www.mindat.org/min-2935.html Mindat, with localities]</ref><ref>[http://www.webmineral.com/data/Northupite.shtml Webmineral]</ref> }}

'''Northupite''' is an uncommon evaporite mineral, with the chemical formula Na<sub>3</sub>Mg(CO<sub>3</sub>)<sub>2</sub>Cl. It occurs as colourless to dark grey or brown octahedral crystals and as globular masses. In synthetic material it forms a series with tychite (Na<sub>6</sub>Mg<sub>2</sub>(CO<sub>3</sub>)<sub>4</sub>SO<sub>4</sub>).<ref name=Mindat/>

It was discovered in 1895 at Searles Lake, San Bernardino County, California by C. H. Northup (born&nbsp;1861) from San Jose, California, for whom Northupite is named.

It occurs associated with tychite, pirssonite at Searles Lake and with shortite, trona, pirssonite, gaylussite, labuntsovite, searlesite, norsethite, loughlinite, pyrite and quartz in the Green River Formation of Wyoming.<ref name=HBM/>

==References== {{reflist}}

{{Commonscat|Northupite}}

Category:Carbonate minerals Category:Sodium minerals Category:Cubic minerals Category:Minerals in space group 203 Category:Minerals described in 1895 {{carbonate-mineral-stub}}