Period 6 element 1783. Its important ores include wolframite and scheelite. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all the non-alloyed metals and the second highest of all the elements after carbon. Also remarkable is its high density of 19.3 times that of water, comparable to that of uranium and gold, and much higher (about 1.7 times) than that of lead. Tungsten with minor amounts of impurities is often brittle and hard, making it difficult to work. However, very pure tungsten, though still hard, is more ductile, and can be cut
Wolfram Saenger Wolfram Saenger Wolfram Saenger (born 1939) is a German biochemist and protein crystallographer. In his research career spanning over 30 years he has worked at the Max Planck Institute for Experimental Medicine, Harvard University (Harvard Medical School) and the Free University of Berlin, where he led the Institute for Crystallography research until his retirement in 2011. A recipient of the Gottfried Wilhelm Leibniz Prize (1987) of the Deutsche Forschungsgemeinschaft, which is the highest honor awarded for achievements in research in Germany, and the Humboldt Prize (1988), he is best known for his research on X-ray crystallography of membrane proteins and