Quiz: Remember the definition of mal de mer?
the most important mineral source of molybdenum, molybdenum disulfide (MoS2). Molybdenite crystals have the same hexagonal symmetry as those of tungstenite (tungsten disulfide). Both have layered structures and similar physical properties; the chief difference is the higher specific gravity of tungstenite. For detailed physical properties, see sulfide mineral (table)