Interpretation of the Group Standard for Pink Synthetic Diamond (Laboratory-Grown Diamond)—Identification and Grading

To standardize the market order of pink laboratory-grown diamond and provide technical support, the China Association for Quality Inspection issued the Association Standard Pink Synthetic Diamond (Laboratory-Grown Diamond)—Identification and Grading (T/CAQI 435—2025) on 1^st July, 2025. The development of this standard holds significant practical importance and fill the domestic standard gap in this field. It helps improve the accuracy of identification and consistency of grading, enhances consumer confidence, and promotes the healthy development of the synthetic diamond industry. This article aims to systematically interpret the core content of the standard, clarifying its specific methods and technical basis for identification and grading. Through systematic research on over 2 000 pink laboratory-grown diamond samples and the application of various technical methods such as UV-Vis spectroscopy, infrared spectroscopy, laser Raman spectroscopy, and photoluminescence spectroscopy, a scientific identification process and a physical reference system for colour grading were established. The standard includes key clauses on identification characteristics, grading conditions, and colour grading procedures, with a focus on addressing technical challenges such as photochromic effects and the influence of overtone colours. The results demonstrate that this standard provides a unified and reliable operational guideline for the identification and grading of pink laboratory-grown diamonds, exhibiting high practicality and promotional value.