Rare earths in phosphorites: Geochemistry and potential recovery

Rare earths are but trace constituents of marine apatite. However, as millions of tones of such apatite are dissolved annually to make phosphoric acid, an opportunity exists for greatly increasing RE output as by-product of fertilizer production. New, complete, quantitative analysis of RE in representative apatite concentrates reveal that the potential for by-product RE equals current production. The RE assemblage in marine apatite is unusual, showing depletion in cerium and relative enrichment in the heavier lanthonons, a favorable distribution for RE technology and utilization.