Vanadium

Vanadium's four common oxidation states give four different colours in solution — yellow, blue, green and violet — which is why Nils Sefström named it after Vanadis, a byname of the Norse goddess Freyja, when he characterised it in 1830. Andrés Manuel del Río had actually found it in Mexico in 1801 but was persuaded by a French chemist that he had only impure chromium and withdrew the claim. Its first mass application was Henry Ford's, who saw a chrome-vanadium steel in a wrecked French race car and built the Model T chassis from it, gaining strength enough to save serious weight. Today most vanadium goes into high-strength low-alloy steel, vanadium pentoxide catalyses the contact process for sulfuric acid, and vanadium redox flow batteries are one of the leading options for grid-scale storage.