Rare earths are among the most critical raw materials on the planet, deeply embedded in the technologies that underpin modern life. Yet few people had even heard of them until the eruption of the US-China trade war thrust them into the limelight.

China confirmed a trade framework with the US lifting curbs on rare earth exports while Washington ends punitive measures targeting Chinese firms.

The announcement offered hope of a reprieve on shortages that have hit American industry, and came after President Trump said he signed a deal with China.