Abstract: New data obtained during the MESSENGER mission has allowed us to better contrain the composition and mineralogy of the mercurian surface. One unique feature of Mercury is its extremely low oxygen fugacity (ƒO2) (Iron Wustite (IW) -7.3 to IW-2.6). At such extreme conditions, elements that exhibit lithophile behavior on Earth can exhibit chalcophile or siderophile behavior, leading to the formation of exotic sulfides and metals. As no samples have been returned from Mercury, it is critical to s…