India, Sept. 11 -- Aluminium may look like a simple business. A company takes bauxite from the ground, turns it into alumina, and then makes aluminium from it. But companies can make more money when that aluminium is turned into useful products such as beverage cans, car parts, battery foil and other specialised products, instead of simply selling the metal.

Hindalco is where this gets interesting. The Aditya Birla Group company is already one of the world's biggest aluminium players, but it is now spending heavily to build new sources of growth. Instead of relying only on selling basic aluminium, the company is putting more money into businesses that can earn more from the same metal. And one of these bets is especially large.

The $...