"A recently discovered carbonatite of Jurassic (?) age, situated on the edge of a rift valley, is described. The carbonatite consists of two elements, a central plug filling the neck of an extinct volcano, and an outer ring of carbonatite surrounding the plug. In places metasomatized Precambrian gneisses lie between the central plug and the outer ring. The overlying volcanic pile has been almost completely removed by erosion. Numerous accessory minerals are present; the most important are pyrochlore (about 63 percent Cb 2 O 5 ), magnetite, and apatite."

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