Light source dependent colour perception in orange red garnets via spectroscopy and colorimetry
The coloration of garnets is governed by transition metal ions and crystal structure. This study established a rapid variety identification method for orange-red garnets based shifts in infrared absorption peaks. We quantified color parameters under standardized illuminants (D<sub>65</sub>, A, and F<sub>2</sub>) using the CIE 1976 L<sup>*</sup>a<sup>*</sup>b<sup>*</sup> space. The results revealed that the Mn/Fe ratio and Fe content critically modulate the hue angle (h<sup>°</sup>) of orange and red garnets. Illuminant A maximises chroma for red varieties, while F<sub>2</sub> light optimally displays orange-yellow garnets. D<sub>65</sub> provides a versatile source for routine identification and evaluation. This integration of crystal chemistry and colorimetry offers actionable strategies for optimising orange-red gemstone presentation.
Authors
- Pohsun Wang (ORCID: https://orcid.org/0000-0003-3908-7230)
- Ying Guo (ORCID: https://orcid.org/0000-0002-7208-4368)
- Meilin Zhu
Institutions
- China University of Geosciences (Beijing) (CN)
- City University of Macau (MO)
Publication Details
- Journal
- Scientific Reports
- Published
- 2025-11-23
- DOI
- https://doi.org/10.1038/s41598-025-28580-8
- Primary Topic
- Mineralogy and Gemology Studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- China University of Geosciences, Beijing
- China University of Geosciences