gems, Ceylon, Sri Lanka, taaffeite, taprobanite, nomenclature

A discussion of the mineralogical nomenclature of taaffeite and taprobanite. Additional abstract: Chemical and crystallographic study of material from Sri Lanka, the U.S.S.R. and China showed taaffeite and taprobanite to be the same mineral, with composition BeMg₃Al₈O₁₆ and hexagonal symmetry. Schmetzer uses the case to examine whether mineral nomenclature should give priority to type material or to an original published description.