Formal discreditation of ‘eosite’, a historic mineral name originally described from Leadhills, Lanarkshire, Scotland

In 1871, ‘eosite’ was described as a lead vanadate/molybdate found on samples from Leadhills in Lanarkshire. The name gained some traction within Scottish mineralogical literature and although listed in nomenclature compilations it is unclear exactly what the term represented. This study outlines the history of the name, its interpretation and the fortuitous discovery of a portion of the type specimen, permitting a modern assessment. Chemical analysis combined with X-Ray microdiffraction of the type specimen identifies the original ‘eosite’ as wulfenite, with minor chromium substitution. This is ultimately of little relevance in the context of geodiversity in Scotland and Leadhills, so to expunge the term from any future work the name ‘eosite’ has been formally discredited by the International Mineral Association's – Commission on New Minerals, Nomenclature and Classification (IMA-CNMNC) Proposal 25-C. This study is a rare situation where the commission has addressed a name for discreditation that is not on the official list.