Formula: Pb6(Te4+O3)5(S6+O3S2–)
Sulphate, tellurium-bearing mineral
Specific gravity: 6.888 calculated for the empirical formula and 6.977 calculated for the ideal formula
Hardness: 2
Streak: White
Colour: Beige
Luminescence: Nonfluorescent under long and short wave ultraviolet light
Solubility: Slowly soluble in concentrated hydrochloric acid at room temperature

Metamorphic environments
Hydrothermal environments

Northstarite is a relatively new mineral, approved in 2019 and to date (May 2022) reported only from the type locality.


At the type locality, the North Star Mine, Mammoth, Tintic Mining District, Juab County, Utah, USA, the mine exploited a polymetallic gold-silver-copper-lead vein deposit emplaced in contact-metamorphosed dolomite, and it was the largest producer of gold in the Tintic district. The principal ore minerals were galena, cerussite and enargite, and the prominent gangue minerals were quartz and baryte.
The northstarite is an oxidation-zone mineral known from only one small specimen. It occurs as short prisms with pyramidal terminations, up to about 1 mm in length, in a vug in massive quartz-baryte-enargite-pyrite. Other secondary minerals found in association with northstarite are adanite, anglesite, azurite, chrysocolla, fluorapatite, plumbogummite, tellurite, zincospiroffite, and an unidentified poorly crystalline copper-tellurite (CM 58,4,533-542)

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