Mercury (element) metals. Alchemists thought of mercury as the First Matter from which all metals were formed. They believed that different metals could be produced by varying the quality and quantity of sulfur contained within the mercury. The purest of these was gold, and mercury was called for in attempts at the transmutation of base (or impure) metals into gold, which was the goal of many alchemists. The mines in Almadén (Spain), Monte Amiata (Italy), and Idrija (now Slovenia) dominated mercury production from the opening of the mine in Almadén 2500 years ago, until new deposits were found at the end of
Period 5 element various oxidation states in minerals. Industrially, molybdenum compounds are used in high-pressure and high-temperature applications, as pigments and catalysts. Molybdenum minerals have long been known, but the element was "discovered" (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele. The metal was first isolated in 1781 by Peter Jacob Hjelm. Most molybdenum compounds have low solubility in water, but the molybdate ion MoO is soluble and forms when molybdenum-containing minerals are in contact with oxygen and water. Technetium is the chemical element with atomic number 43