Gautam Adani is world’s 9th richest person began with a port on India’s west coast in the 1990s and an abiding friendship with a politician who’s now prime minister.

The port brought in coal, liquefied gas and palm oil — and so Adani got into them and adjacent businesses.

Birla, who turns 55 this month, built on that when he bought the US-Canadian Novelis Inc. in 2007 to become the world’s largest aluminum-rolling company.

Adani, pursuing his strategy of entering adjacent industries, is challenging Birla in the latter's family turf of cement.

Birla-controlled UltraTech Cement Ltd. recently announced a capital expenditure of 129 billion rupees ($1.7 billion) to increase its cement capacity by 22.6 million tons per annum.

Meanwhile, Adani is paying almost double that per ton for taking over an estimated 73 million tons per annum capacity this year at the two Holcim companies, Ambuja Cements Ltd. and ACC Ltd.

If Adani is going to buy scale at a premium, Birla will build cheap. The game is on. Swipe up for next story.