Melilitolites; a new scheme of classification

Abstract

Arsrnecr A new scheme of classification is proposed for metilite-bearing plutonic rocks with more than l07o melilite and less than 507o pimary carbonate phases, based on the absolute modal abundances of the dominant minerals. Melilitolite is retained as a general root-name for all such rocks. Previous definitions of terms used in the classification of these rocks, including afrikandite' kugdite, okaite, turjaite and uncompahgrite, are modified in order to provide root-names for melilirolites. A new rock-name, ultramelilitolite, is proposed as a specific root-nams f6l samples with more than 657o melilite. The use of multiple root-na.mes and the problems associated with the use of mineral modifiers in rock nomenclature are discussed.