With vanadium we find an example of an unsung industrial hero. The obscure metal is an integral ingredient in many different alloys where it provides resistance to corrosion, strength and malleability but the pure metal is too costly to feature much of a need in commerce.

Organic molecules that involve vanadium are colorful as well as toxic and a few species make use of such a combination to warn predators in analogous fashion to poison dart frogs and such (though in this case utilizing different chemistry). 

The strips of pure vanadium included in this cube appear as though cast from some otherworldly marriage of metal and turquoise or emerald. The explanation however is a little more sober: in the world of chemistry vanadium is famous for the attractive panoply of colors made by its compounds. In this case, just ordinary water vapor from the atmosphere is all that's needed to turn the metal several shades of green and blue from a micrometers-thick layer of exotic sounding vanadium hexa-aqua.