Of “practical advances” in world history, “nothing is comparable to (mankind’s) complete mastery over enormous masses of steel and iron”.

So wrote the English author H G Wells in 1920.

He was influenced particularly by the growth of Europe and North America from the 1860s, when large-scale steel manufacturing began.

But his comment applies equally to the current growth of China, India, Brazil and others.

Behind this growth lies coking coal, indispensable for modern steel production.

The world’s largest coking-coal exporter is Australia. The next largest exporters are the US and Canada.

Together, these three countries exported 220 million tonnes in 2011, expected to reach at least 270 million tonnes by 2015 (over 80 per cent of total coking-coal exports).

Waiting in the wings are three countries whose coking-coal exports are small, but growing: Mongolia, Mozambique and Indonesia.

By 2015, coking-coal exports from these countries should reach at least 30 million tonnes.

Barring a major world economic slow-down, the outlook for coking-coal exports is favourable.

Global steel production will increase by at least 50 per cent in the next 15 years, according to BHP Billiton.

Current coking-coal exporters will be the beneficiaries of this growth.

And exporters are being assisted by the recent turnaround in China from exporter to importer.

Substitutes offer some threat to steel: for example, “carbon fibre is replacing steel and aluminium in products ranging from aeroplanes to mountain bikes” (The Economist (19 April 2012).

But overall, carbon fibre is still far from being a cost-effective competitor to steel.