Molybdenum is a silvery-grey metal with a Mohs hardness of 5.5. It has a melting point of 2,623 C (4,753 F); of the naturally occurring elements, only tantalum, osmium, rhenium, tungsten, and carbon have higher melting points.[6] Weak oxidation of molybdenum starts at 300 C (572 F). It has one of th