Hylbrownite
Hylbrownite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula Na₃MgP₃O₁₀·12H₂O.
It crystallizes in the monoclinic crystal system (space group P2_1/n). It is a member of the Kanonerovite structural group.
Key properties: specific gravity 1.81; White streak; Vitreous luster; optically biaxial.
IMA symbol Hbw, IMA status: approved, named in 2010.
Found as a secondary mineral in the oxidized zone of a polymetallic sulfide deposit.
It is found associated with Conichalcite, chrysocolla, cuprite, malachite, azurite, quartz, goethite.
The mineral was named to honor Henry Yorke Lyell Brown (1844-1928), Government Geologist of South Australia from 1882 to 1912, who authored the first geological map of the whole colony in 1899.