Abstract
This study investigates the Esoteric Buddhist murals in Cave 465 of the Mogao Caves, Dunhuang. Widespread discolouration renders the present colours black, grey, dark-toned or mottled white. Previous iconographic identifications relied solely on morphological features such as mudras, postures and ritual implements, without supporting colour evidence. Microscopic and spectroscopic analyses were undertaken to identify pigments, characterise colouring techniques and infer the original colours. The inferred colour data were compared with textual iconographic prescriptions and conventional Thangka colour schemes to explore their correlations. The murals utilise mineral pigments including hematite, red lead, cinnabar, orpiment, realgar, azurite, atacamite, gypsum and calcite, alongside the organic pigment lac dye. Superimposed painting, glazing and colour mixing were widely adopted. The colour schemes of the Five Dhyani Buddhas, several Vajra deities and their consorts, and protective deities show similarities to textual records, while blue pigments were applied in more diverse and complex ways, yielding not a uniform blue but blues of varied tones. The results of this study provide colour evidence for deity identification in Cave 465, an important reference for research on Tantric Buddhist imagery in the Dunhuang grottoes, and a scientific basis for mural colour reconstruction.