Dutch Marquise: Open Geometry Specification

An open, versioned, machine-readable specification for the Dutch Marquise diamond cut and its companion the French Marquise: outline, faceting pattern, certificate nomenclature, and length-to-width ratio, with every claim sourced. Published by Stienhardt & Stones, which cuts these stones in-house. The term Dutch Marquise is a trade name, not an officially recognized gemological shape; grading laboratories describe the geometry as a modified marquise brilliant.