Element 76 in our International Year of the Periodic Table series is osmium. Osmium is the densest element in the periodic table and is used in fountain pens and microscopy.
Osmium is the densest element in the periodic table, with a density about twice that of lead’s and 23 times that of water. Its density is very close in value to that of iridium but just edges it out for the title of most dense.
Alloys of osmium and iridium are used for their hardness in the tips of fountain pens. Osmium also finds use in electrical contacts where resistance to wear is required.
Osmium tetroxide is used as a staining agent in some types of microscopy to make clearer images. This compound has also been used in fingerprint detection.
Remember, you can keep track of all of the previous entries in this series on the site here, or on the Royal Society of Chemistry’s dedicated page.
