Gadolinite rhenium

L. Rhenus, Rhine) Discovery of rhenium is generally attributed to Noddack, Tacke, and Berg, who announced in 1925 they had detected the element in platinum ore and columbite. They also found the element in gadolinite and molybdenite. By working up 660 kg of molybdenite in 1928 they were able to extract 1 g of rhenium. 

Rhenium (Re, [Xe]4/145river Rhine. Discovered (1925) by the German chemists W. Noddack, I. Noddack-Tacke and O.C. Berg in minute amounts in a sample of gadolinite (a basic silicate of Be, Fe and lanthanides). Silvery-white metal. 

Rhenium was the last naturally occurring chemical element to be discovered in 1925 by Noddack, Tacke, and Berg in the mineral gadolinite. The name of this extremely rare element (the estimated occurrence in the earth s crust is about 0.7 ppb ) is derived from the Rhine river. Residues from the processing of molybdenum ores represent the main source of the metal. 

Rhenium does not occur alone in nature in elemental form. It is found in trace quantities in a number of minerals such as columbite, gadolinite, molybdenite, tantalite, wolfranite, and many platinum ores. Its average concentration in earth s crust is 0.0007mg/kg. 

Rhoiinm — (L. Rhenus, Rhine), Re at. wt. 186.207(1) at. no. 75 m.p. 3186°C b.p. 5596°C sp. gr. 21.02 (20°C) valence -1, -h1, 2,3, 4,5, 6, 7. Discovery of rhenium is generally attributed to Noddack, Tacke, and Berg, who announced in 1925 they had detected the element in platinum ores and columbite. They also found the element in gadolinite and molybdenite. By working up 660 kg of molybdenite they were able in 1928 to extract 1 g of rhenium. The price in 1928 was 10,000/g. Rhenium does not occur free in nature or as a compound in a distinct mineral species. It is, however, widely spread throughout the earth s crust to the extent of about 0.001 ppm. Commercial rhenium in the U.S. today is obtained from molybdenite roaster-flue dusts obtained from copper-sulfide ores mined in the vicinity of Miami, Arizona, and elsewhere in Arizona and Utah. Some molybdenites... 

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