#carbonatite

Richterite Phenocryst in a Carbonatite

CAMBORNE HOMING IN ON HEAVY RARE EARTHS

Examinations of an unusual carbonatite deposit in Malawi could help mining companies track down heavy rare earth elements. Simon Frost reports.

Rare earth elements (REEs) may not be as scarce as the name suggests, but China has the monopoly on their supply. Now pivotal research undertaken in Malawi and led by the Camborne School of Mines, UK, could help to make REEs a viable prospect worldwide, as their demand in applications as diverse as consumer electronics, power generation and anti-fraud technologies continues to grow.  

While relatively abundant, REEs are typically distributed in low concentrations, making them difficult to extract cost-effectively. In recent years, China has become the dominant force in the supply of REEs, with typical estimates ranging between 90–95% of the global market share (see Materials World, February 2015, page 50). The USA, once the global leader in REE supply and capable of fulfilling all its domestic needs, now imports 87% of its REEs from China, owing to unmatchable low costs.

As part of global efforts to resolve this supply problem, a new study led by Dr Sam Broom-Fendley at Camborne examines the conditions under which REEs – in particular, the scarcer heavy rare earths (HREEs) – are concentrated in carbonatite rock formations at the Songwe Hill Rare Earth Project in Malawi. HREEs such as dysprosium, europium and terbium are increasingly being used in lighting, anti-fraud and safety technologies.