Many extrusive carbonatites are now recognised as having been rapidly erupted directly from the mantle. They carry mantle debris, typically occur around maars and may be our most direct 'window' on the carbonate involved in mantle metasomatism. They increase the connection between carbonatites and kimberlites, which are now also widely regarded as driven by volatiles, especially mantle CO 2 . However, they also tend to be highly permeable and to alter and recrystallize easily. Thus the

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... ation of primary igneous carbonate can be difficult. Nevertheless, it is critical because if it is possible to find pristine compositions, these are likely to be that of the carbonate in the mantle, free of the fractionation and subsolidus alteration ubiquitous in intrusive carbonatites. The main aims of this study were to determine the trace element carbonate compositions in the pyroclastic carbonatites to establish if igneous calcite is compositionally distinct from low temperature material and to compare the composition of extrusive calcite to that of calcite from mantle xenoliths. Other major hosts for REE in carbonatites and mantle rocks, including apatite, pyrochlore, clinopyroxene and silicate glass were also analysed. Two contrasting carbonatites were analysed. Kaiserstuhl, Germany is a well-known alkaline and carbonatite complex, which contains extrusive calcite carbonatite lapilli tuffs, intrusive carbonatites and a variety of intrusive and extrusive alkaline silicate rocks. Intrusive carbonatite has been known there for a long time and the more recent discovery of lapilli tuff was key to establishing that carbonate melt droplets can be erupted (Keller, 1981) . It is a good example of what geologists are looking for in establising new carbonatite localities. The second example is a much more recent discovery of carbonatitic maar volcanism associated with nephelinitic and melilitic volcanism at Calatrava, Castilla-La-Mancha, Spain (Bailey et al., 2004). Calatrava is potentially one of the world's largest carbonatitic provinces with over 200 volcanic centres, many containing carbonate coerupted with alkaline silicate rocks and (in contrast to Kaiserstuhl) with mantle debris. Maars are the major vent form and thus the eruption style is similar to kimberlite. No intrusive carbonatite has been found at Calatrava. Analyses of the calcite and associated minerals were made by Cameca SX 50 electron microprobe and by LA-ICPMS using a Thermo Elemental PlasmaQuad 3 ICPMS coupled to a frequency quintupled Nd:YAG laser system operating at 213 nm (New Wave Research). Spatially-resolved analysis is essential to be able to discriminate between multiple generations of carbonate. The EPMA