Everything we can see and touch, and quite a lot that we can’t as well, is made of tiny particles called atoms. Some substances, like particles of this iron, contain only one kind of atom. Iron is an ...

A chemical element is one of those squares on the periodic table that adorns many a classroom wall. Sure. But what is an element really? It is a more subtle question that you might realise. To get to ...

Diamond is the only gem with a single element. Diamonds are formed in the Earth’s mantle, at depths exceeding 120 km (75 miles), under extreme temperatures and pressures. Over a billion years, the ...