Builders like angular sand of the kind found on riverbeds. Wind action in deserts results in rounded grains that are too smooth and too small to bind well in concrete. Our need for concrete is such that we make almost 2 cubic metres worth each year for every man, woman and child on the planet.īut what of those oceans of sand stretching from the Atlantic to the Persian Gulf – the Sahara and the Arabian Desert? The wrong kind of sand, unfortunately. Of the 15 to 20bn tonnes used annually, about half goes into concrete. Global production has risen by a quarter in just five years, fuelled by the insatiable demands of China and India for housing and infrastructure. Sand is second only to water as a natural material extracted by humans, and our society is built on it, quite literally. Enough material to build a wall 27m high and 27m wide around the equator. The world consumes between 30 and 40bn tonnes of building aggregate a year, and half of this is sand.
Our insatiable appetite for new buildings, roads, coastal defences, glass, fracking, even electronics, threatens the places we are designed by evolution to love most. Yet sand in the right places is anything but infinite.
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