This page gathers the stones in our collection that are accompanied by a report from GUILD, one of the independent gemmological laboratories whose documentation we accept. A laboratory report is a technical record rather than a valuation: it identifies the species and variety, records weight, measurements and cut, and — where the laboratory undertakes such determinations — comments on geographic origin and on whether the stone shows evidence of treatment.
Two varieties appear here at present: Mozambique Ruby and Chrysoberyl. Ruby is the red variety of corundum, its colour driven by chromium, and it is prized for saturation and for the way strong chroma reads at a distance. Chrysoberyl is a separate mineral species altogether, typically encountered in yellow to greenish-yellow tones, and is notable for its exceptional hardness and crisp, bright lustre.
When choosing between them, weigh the character of the colour you want, the durability required by the intended setting, and the specific wording of the accompanying report. We recommend reading each individual listing alongside its report, since the details that matter most — origin commentary and treatment disclosure — are stated there stone by stone.
