The Distinctive Mineralogy of Carbonatites

Abstract

The mineralogy of carbonatites reflects both the diversity of the sources of their parent magmas and their unusual chemistry. Carbonatites contain diverse suites of both primary magmatic minerals and later hydrothermal products. We present a summary of the variety of minerals found in carbon-atites, and note the economic importance of some of them, particularly those that are major sources of “critical elements”, such as Nb and rare earth elements (REEs), which are essential for modern technological applications. Selected mineral groups are then discussed in detail: the REE carbonates, the alkali-rich ephemeral minerals that are rarely preserved but that may be important in the petrogenesis of carbonatites and their metasomatic haloes in adjacent rocks, and the Nb-rich oxides of the pyrochlore supergroup.