Magnesite is much rarer at MSH, than siderite, its Fe-rich member of the magnesite series. Color is usually pale grayish green. Luster is vitreous to dull. Diaphaneity is transparent. Crystal Habits include modified rhombohedra to 2mm.
Fracture is conchoidal.
Hardness is 3.5 - 4.5. Streak is white. Associated Minerals include calcite, marcasite, muscovite, pyrite, quartz and siderite.