One of the bestselling business books of the last year has been MATERIAL WORLD by @EdConwaySky, Economics and Data Editor at Sky News. It's a study of 6 materials that have gone to make our modern world - sand, salt, iron, oil/gas, copper and lithium - and argues that the way we manage them will shape our future. There are lessons too, about how a country that loses its technological edge in any of these key materials and their products can place itself in peril. (A lesson we in the UK might take on board in these uncertain times.) In the 19th century, Britain made the finest glass in the world - from sand, of course - but over the years allowed its manufacturing prowess to wither and Germany to take the technological lead. As Ed told us, that led to the great Glass Famine of 1914, a true matter of life and death.