Molybdenum (Mo) is the 42nd element on the periodic table. It is a silvery metal and has the sixth highest melting point of any elements, demonstrating its potential uses in construction and metals.Molybdenum was discovered by Carl Welhelm Scheele, a Swedish chemist, in 1778 in a mineral known as molybdenite (MoS2) which had been confused as a lead compound. Molybdenum was isolated by Peter Jacob Hjelm in 1781. Today, most molybdenum is obtained from molybdenite, wulfenite (PbMoO4) and powellite (CaMoO4). These ores typically occur in conjunction with ores of tin and tungsten. Molybdenum is also obtained as a byproduct of mining and processing tungsten and copper.There was no viable use of Molybdenum for over a century. This was due to its scarcity and difficulty in acquiring and extracting the pure element. Early molybdenum steel alloys showed great promise in their increased hardness, but efforts to manufacture them on a large scale were hampered by inconsistent results and a tendency toward brittleness and recrystallization. In 1913, Frank E. Elmore developed a flotation process to recover molybdenite from ores; flotation remains the primary isolation process today.