Hezuolinite
Hezuolinite is an IMA-recognized mineral species in the silicate class, with the chemical formula (Sr,REE)₄Zr(Ti,Fe³⁺,Fe²⁺)₂Ti₂O₈(Si₂O₇)₂.
It crystallizes in the monoclinic crystal system (space group C2/m). It is a member of the Chevkinite structural group.
Key properties: Mohs hardness 5.5–6; specific gravity 4.28; Dark brown streak; Resinous luster; optically biaxial.
IMA symbol Hez, IMA status: approved, named in 2010.
Found in a series of alkaline volcanic and intrusive igneous rocks, in association with aegirine nepheline syenite.
It is found associated with Microcline, nepheline, aegirine, biotite, eudialyte, rinkite, titanite.
The mineral was named to honor He Zuolin (1900-1967), for his contributions to optical mineralogy and rare-earths mineralogy in China. Hezuolinite corresponds to the previously discredited “saimaite”.