Meniaylovite
Meniaylovite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ca₄AlSi(SO₄)F₁₃·12H₂O.
It crystallizes in the cubic crystal system (space group Fd3). It is a member of the Chukhrovite structural group.
Key properties: specific gravity 2.25; Vitreous luster.
IMA symbol Myl, IMA status: approved, named in 2002.
A product of the alteration of volcanic rocks by fumarole gases.
It is found associated with Malladrite, hieratite(?), ralstonite, anhydrite, gypsum, hematite (Tolbachik); anhydrite, bassanite, gypsum, jarosite, anatase, hematite, opal, ralstonite.
The mineral was named to honor Russian volcanologist Igor Aleksandrovich Meniayloy (1937-1993), for his study of the geochemistry of exhalations of the Tolbachik Main Fracture Eruption.