Material World

Conway, an economics journalist, traces six materials that industrial civilisation depends on: sand, salt, iron, copper, oil and lithium. For each he follows the physical supply chain from extraction through processing to end use, visiting mines, refineries, foundries and fabrication plants.

The reporting produces specific and unexpected findings. Silicon for semiconductors comes overwhelmingly from a single quartz deposit at Spruce Pine in North Carolina, whose purity has no substitute. Salt is the input to chlorine and sodium hydroxide, which are required for most industrial chemistry including semiconductor manufacture. Copper ore grades have fallen so far that miners now move enormous volumes of rock for each tonne, which sets a floor on the energy cost of electrification. Lithium processing, as distinct from lithium mining, is concentrated in China to a degree that mining diversification does not address.

Conway's argument is that the physical economy has become invisible to the people who write about the economy, that services and software rest on material flows nobody tracks, and that supply chains have concentration points which do not appear in trade statistics because the volumes are small relative to their importance. He connects this directly to energy transition, arguing that the material requirements of electrification are large and that the processing capacity, not the reserves, is the binding constraint.

The book is journalism and does not attempt the quantitative rigour of Smil, whose work covers similar ground. It is more readable and more current, and its supply chain reporting is its distinct contribution.