The researchers tracked the formation of these supermountains throughout Earth’s history using traces of zircon with low lutetium content -- a combination of mineral and rare earth element only found in the roots of high mountains where they form under intense pressure. The study found the most giant of these supermountains only formed twice in Earth’s history -- the first between 2,000 and 1,800 million years ago and the second between 650 and 500 million years ago. Both mountain ranges rose during periods of supercontinent formation.