As it’s the International Year of the Periodic Table, I decided to revisit this old timeline of element discoveries I put together five years ago. The old version was a little in need of visual improvement, as well as updating to include the element discoveries confirmed since 2014.
The timeline highlights the countries in which all of the 118 elements were discovered. In some cases this differs from the nationality of the person who discovered it; e.g. Marie Curie was Polish, but discovered polonium while working in France. Where an element was discovered concurrently in more than one country, both countries’ flags are shown.
A number of sources were used to piece together the dates, but they’re primarily from the Royal Society of Chemistry’s periodic table. Other sources used were John Emsley’s ‘Nature’s Building Blocks’, and this excellent periodic table of element discoveries by Jamie Gallagher.
Feedback on the original post was invaluable in ensuring that some dates were corrected for this version. If you spot some that you think look incorrect, please do point it out in the comments below.