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The unmetamorphosed Neoproterozoic dykes of the continental intraplate alkaline magmatism studied in Southern Karnataka consist of analcime-tinguaites, tinguaites, bostonites and solvsbergites. The analcime-tinguaites, tinguaites and bostonites display pyroxene trends typical of alkaline rocks; the cores of the phenocrysts containing more diopside whereas the rims contain more hedenbergite and aegirine and the groundmass clinopyroxenes have the highest aegirine contents. The pyroxene trends of the rocks are similar, indicating that the melts they formed from had similar fugacities of oxygen and/or similar peralkalinities. The absence of reverse zoning indicates that the melts were not intermixed. The K-feldspar is either K-rich and Na-poor sanidine or orthoclase and is zoned with respect to sodium and sometimes also barium. The plagioclase is almost pure albite.