Magnesiocanutite
Magnesiocanutite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Na MnMg₂[AsO₄]₂[AsO₂(OH)₂].
It crystallizes in the monoclinic crystal system (space group C2/c). It is a member of the Alluaudite structural group.
Key properties: Mohs hardness 2.5; specific gravity 3.957; White to very pale pink streak; Vitreous luster; optically biaxial.
IMA symbol Mcan, IMA status: approved, named in 2016.
From the oxidation of native arsenic and other As-bearing primary phases, followed by later alteration by saline fluids derived from evaporating meteoric water under hyperarid conditions.
It is found associated with Anhydrite, canutite, halite, lavendulan, magnesiokoritnigite.
As the Mg analogue of canutite with Mg rather than Mn dominant in the M2 site.