The jagged 23-kilometer-long scar that the gigantic rig has left for mining zircon — which is used in ceramics and the building industry — is so big that it is visible from space.

Amid a deafening din, the massive machine sucks up thousands of tons of mineral sands an hour, moving forward on an artificial lake created with water pumped from deep underground.

It is now tearing through the dunes of Lompoul — one of the smallest and most beautiful deserts in the world — a tourist hot spot by the endless beaches of Senegal's Atlantic coast.