Ruthenium is a 'sort of' precious metal that is a useful catalyst and alloy. It is toxic and smells like ozone, says Allan Blackman from AUT in ep 73 of Elemental.

Ruthenium is a rare transition metal produced mostly as a by-product of nickel mining.

It is not widely used industrially, although it is found in some catalysts and alloys. It is more useful in the chemistry laboratory, where it has helped several chemists win Nobel Prizes.

Ruthenium is toxic and if you have the bad fortune to be exposed to it, it smells of ozone says Professor Allan Blackman from the Auckland University of Technology, in episode 73 of Elemental.

Go to this episode on rnz.co.nz for more details