Update of Color-Grading for GRS-type "Pigeon's Blood" Borderlines
Introduction of two new color-descriptors; “Vivid Red to Deep Red” and “Intense Red to Vivid Red”
After collecting valuable feedback from the trade gathered at GRS public seminars, trade shows and symposiums, GRS announces that it is further subdividing the field of colors that are covered by the term GRS-type “Pigeon’s Blood” by introducing two new color grades. This will allow a better understanding and classification of rubies falling under this category.
This new system has become effective in November 2017. The graph below visualizes the changes made in regard to the new color grades “Vivid Red to Deep Red” and “Intense Red to Vivid Red”.

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