Mariinskite grains (green) in the matrix of mica chromite. The photo size is 2 mm by the base, polished section. The image is published in an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( https://creativecommons.org/licenses/by/4.0/ ). — Photo: Khiller, V. · CC BY-SA 4.0
Mariinskite
Mariinskite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula BeCr₂O₄.
It crystallizes in the orthorhombic crystal system (space group Pnma). It is a member of the Olivine structural group.
Key properties: Mohs hardness 8.5; specific gravity 4.25; Pale green streak; Vitreous luster; optically biaxial.
IMA symbol Mii, IMA status: approved, named in 2011.
Replacing low-Al chromite of chromitite lens in serpentinite, probably of metasomatic origin.
It is found associated with Fluorophlogopite, eskolaite, dravite-fluordravite, chromite.
The name is derived from the locality from which the first specimens were collected.