Igneous and sedimentary ‘limestones’: the puzzling challenge of a converging classification

Abstract The vast majority of extrusive carbonatites are calcitic rocks which may be confused with sedimentary limestones, thus requiring a disambiguation criterion. Extrusive classified based on quantitative criteria that tend to avoid genetic mechanisms. Carbonatite nomenclature is in progress but regulated by the International Union Geological Sciences norm for igneous rocks. Carbonate rock mainly Dunham, Embry and Klovan, Sibley Gregg classification systems. These limit description types from various depositional mechanisms makes comparison difficult. Igneous carbonate display no apparent differences field at meso–micro-scale. They layered, massive crystalline or show discrete clasts matrix, make both resemble one another. study analyses situations inconsistencies most common. Adopting these guidelines increase confidence, reliability value petrographic lithologies. This poses challenging target. Can using same approach used vice versa? So far, scheme chosen has been arbitrary limited aim being undertaken. authors start an unexperienced dialogue first time between volcanologists sedimentologists examining range volcaniclastic textures each other.