Ruthenium is a chemical element with the symbol (Ru) and an atomic number of 44. It is a rare transition metal that belongs to the platinum group and like other metals of the platinum group it is inert to most chemicals. It is found as a minor component of platinum ores and has a yearly production rate of only 12 tons worldwide. The main application for ruthenium is for the production of wear resistant electrical contacts and the production of thick film resistors. It is also used in some platinum alloys in a minor application. Because of its ability to harden palladium and platinum it is used in these metals to produce wear resistant electrical contacts. In this instance only thin plated films are used to create the necessary wear resistance. It also has a lower cost than rhodium which makes its main application plating electrical contacts. Another example of its use is in certain jewellery items such as gold to increases its stability by improving the properties of the alloy.
