Northstarite
An immensely rare lead tellurite-thiosulfate discovered in 2019 at Utah's North Star mine.
Intro adapted from Wikipedia (CC BY-SA).
Northstarite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula Pb₆(Te⁴⁺O₃)₅(S⁶⁺O₃S²⁻).
It crystallizes in the hexagonal crystal system (space group P6_3).
Key properties: Mohs hardness 2; specific gravity 6.977; White streak; Adamantine luster; optically uniaxial.
IMA symbol Nsr, IMA status: approved, named in 2019.
An oxidation-zone mineral in a vug in massive quartz-baryte-enargite-pyrite in a polymetallic (Au-Ag-Cu-Pb) vein deposit emplaced in contact-metamorphosed dolomite.
It is found associated with Anglesite, azurite, chrysocolla, fluorapatite, plumbogummite, tellurite, zincospiroffite, adanite.
The name refers to the mine that contained the studied material.