2008/06/01 by F. Hatert, Frédéric Hatert, E. A. J. Burke +1 · 2 citations
Engineering · Materials Science · #Crystal Structures and Properties #Geology #Metal Extraction and Bioleaching #X-ray Diffraction in Crystallography
paper · doi:10.3749/canmin.46.3.717
crossref issued 2008/06/01 · crossref published 2008/06/01 · crossref published-print 2008/06/01 · openalex publication_date 2008/06/01 · crossref created 2008/08/29 · crossref deposited 2011/02/07 · openalex created_date 2025/10/10 · crossref indexed 2026/07/31 · openalex updated_date 2026/08/01
Mineralogical nomenclature in solid-solution series follows a system that has been called the 50% rule, more correctly the 100%/n rule or the dominant-constituent rule, in which the constituents are atoms (cations or anions), molecular groups, or vacancies. Recently developed systems of nomenclature for the arrojadite and epidote groups have shown that a group of atoms with the same valency state must also be considered as a single constituent to avoid the creation of impossible end-member formulae. The extension with this dominant-valency rule is imposed by all cases of coupled heterovalent-homovalent substitutions. End members with a valency-imposed double site-occupancy may result from single-site heterovalent substitutions and from coupled heterovalent substitutions at two sites where there is a disparity in the number of these two sites.