Outstanding orange-red bonazziite crystals associated to dark-red pararealgar from a new locality in China, the Lanmuchang mine (Qianxi'nan Prefecture, Guizhou Province), famous for its thallium minerals. Bonazziite (IMA 2013-141) is a polimorph of realgar and pararealgar. — Photo: David Hospital · CC BY-SA 4.0
Bonazziite
Bonazziite is an IMA-recognized mineral species in the sulfide class, with the chemical formula As₄S₄.
It crystallizes in the monoclinic crystal system (space group C2/c).
Key properties: Mohs hardness 2.5; specific gravity 3.542; Dark orange streak; Resinous luster.
IMA symbol Bzz, IMA status: approved, named in 2013.
Low-temperature hydrothermal mineral probably formed while the system had direct involvement of magmatic volatiles.
It is found associated with Realgar, sulfur, wakabayashilite, alacránite, non-stoichiometric As4S4+x sulfides, stibnite, calcite.
The mineral was named to honor Paola Bonazzi (b. 1960), Professor in Mineralogy, University of Florence, Italy.