44 Ru 101.07

Ru - Ruthenium

See metal norms for Ruthenium

Chemical Element Ruthenium Melting Point °C 2310
Chemical Symbol Ru Boiling Point °C 3900
Atomic Number 44 Density g/cm3 12.4
Atomic Weight 101.07 Oxide Ru2O3


Ruthenium is a lustrous, silvery metal of the platinum group, and a member of group 8 of the Periodic Table. It is the 74th most abundant element within the Earth’s crust. Ruthenium is unaffected by air, water, and acids, but dissolves in molten alkalis. Ruthenium is a rare transition metal, and therefore, similarly to osmium and iridium, is extremely expensive.


In 1807, the Polish chemist, Jedrzej Andrei Sniadecki, based at the University of Vilno, began investigating some crude platinum ores from South America, resulting a year later in the discovery of a new metal, which he called vestium, after the asteroid Vesta, which had been first observed the previous year. Sniadecki published his finding in a Russian journal, but he dropped his claim of discovering a new element when a group of leading French chemists had had failed in finding any vestium when they repeated his experiment. In 1825, Jons Jacob Berzelius and Gottfried Wilhelm Osann were investigating some platinum retrieved from the Ural Mountains in Russia. Although Berzelius claimed to have found nothing new, Osann claimed to have found three new metals, including ruthenium, which was proved to be a new metal in 1840 by a former colleague of Osann’s, Karl Karlovich Klaus working at the University of Kazan. He showed that Osann’s was very impure, and set about extracting and purifying his own sample and investigating its properties. The result is that today Klaus is credited with the discovery, but Osann’s name ruthenium, the Latin word for Russia, has remained.


Ruthenium is a very rare metal, with only 12 tonnes per year being extracted, and with a global reserve at around 5,000 tonnes. Similarly to most other platinum group metals, it is mined as a by product of nickel.


Ruthenium acts as a catalyst in some platinum alloys, but the majority of it is used within the electrical industry (51%), where it is used for electrical contacts and chip resistors, and a further 40% used in the chemical industry.  Other uses are in dye sensitized solar cells, where it is used to turn sunlight directly into electricity, and in the anodes for chlorine production in electro-chemical cells. Finally some ruthenium is used in the alloying of platinum and titanium, for example to make platinum harder for jewellery making, and is added to the titanium for deep water pipes to increase corrosion resistance.

  • Emsley, John. Nature’s Building Blocks, An A-Z Guide to the Elements, New Edition, Oxford University Press, 2011
  • Gray, Theodore. The Elements, A Visual Exploration of Every Known Atom in the Universe, Black Dog & Leventhal Publishers, Inc, NY, 2009
  • Stwertka, Albert. A Guide to the Elements, 3rd Edition, Oxford University Press, 2012