Steely. A word often associated with cold, dispassionate, hardened, and imperturbable. Not so the industry’s investors: as China’s building boom has slowed, they have skedaddled, leaving the share prices of some of Asia’s biggest producers languishing well below book value. That is hard to justify.

At first glance, it does look grim. Mills in China, producer of nearly half of all steel and consumer of a roughly similar amount, are turning to pig farming, among other ventures, for profits. Collectively, the industry has turned a profit of nearly $5bn in the first quarter of 2011 into a $600m loss this year, even as production reaches record levels, China Iron and Steel Association data shows.

That does not however fully explain why giants such as Posco of Korea, Nippon Steel and China’s Baoshan and Angang trade at an average three quarters of book value – about half their 10-year average. That puts companies where property, equipment and stock account for more than half of book not far above liquidation value.