Molybdenum History
In ancient times a number of substances were collectively known by the Greek word ‘molybdos’, which means lead-like. The mineral molybdenite, which is the predominant source of molybdenum, was one of these substances. In 1778 the Swedish scientist Carl Wilhelm Scheele discovered, that molybdenite was the sulfide of a previously unknown metal which he named molybdenum.

Wills Saint Claire - First automobile
constructed with Mo steels (Courtesy
of Climax Molybdenum Company)
Molybdenum was not discovered until the latter part of the 18th century, and does not occur in the metallic form in nature. Despite this, its predominant mineral - molybdenite - was surely utilised in ancient times but would have been indistinguishable from other similar materials such as lead, galena and graphite. Collectively, these substances were known by the Greek word "molybdos", which means lead-like.
A 14th century Japanese sword has been found to contain molybdenum. However, it was not until 1778 that the Swedish scientist, Carl Wilhelm Scheele, was able positively to identify molybdenum. He decomposed molybdenite by heating it with nitric acid and by heating it in air to yield a white oxide powder. Shortly thereafter, in 1782, Peter Jacob Hjelm reduced the oxide with carbon to obtain a dark metallic powder which he named "molybdenum".
Molybdenum remained mainly a laboratory curiosity throughout most of the 19th century until the technology for the extraction of commercial quantities became practical. In 1891, the French company Schneider & Co. first used molybdenum as an alloying element in the production of armour plate. It was quickly noted that, with a density of only slightly more than half that of tungsten, molybdenum was an effective replacement for tungsten in numerous steel alloying applications.
World War I caused tungsten demand to soar and severely strained its supply. As a direct result, molybdenum was substituted for tungsten in many hard and impact resistant steels. The resulting increased demand initiated an intensive search for new sources of molybdenum supply, culminating with the development of the massive Climax deposit in Colorado, USA and its initial operation in 1918.
The end of the war and the consequent reductions in demand triggered research efforts to develop new civilian applications for molybdenum. A number of new low-alloy molybdenum automotive steels were soon tested and accepted. The big breakthrough however, occurred in the 1930s with the determination of proper temperature ranges for the forging and heat treatment of molybdenum-bearing high-speed steels. From this beginning, research eventually developed a full understanding of how molybdenum imparts its many cost-effective benefits as an alloying element to steels and other systems.
By the end of the 1930s, molybdenum was a widely accepted technical material. The conclusion of World War II in 1945 once again brought increased research investment to develop new civilian applications, and the post-war reconstruction of the world provided additional markets for structural steels, many of which already contained some molybdenum.
The years from 1945 to the present have seen a dramatically expanding range of applications for molybdenum, its alloys and its compounds. Rising demand has been comfortably balanced by new sources of assured supply and by new processing technologies with superior recovery rates.
Although steels and cast iron comprise the single biggest market segment, molybdenum's diversity has also proven invaluable in superalloys, nickel base alloys, lubricants, chemicals, electronics and many other applications.