Spectral and biomolecular evidence from fibers of two Hexi Corridor ancient turquoise mining sites

Identifying ancient textile fibers is crucial for conservation and reflects ancient subsistence and economic practices. This study investigates fiber and textile fragments from two neighboring turquoise mining sites in the Hexi Corridor, dating to the Early Western Zhou and Spring and Autumn periods. Using ultra-depth-of-field microscopy, scanning electron microscopy (SEM), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, we found morphological analysis alone insufficient for identification. Fourier self-deconvolution and Gaussian-fitting of spectral data revealed consistent protein secondary structures, while mass spectrometry confirmed identical primary structures, indicating that fibers from both sites belong to the same wool species. The presence of sheep wool textiles demonstrates continuity in animal fiber use across different periods, offering material evidence of pastoral economies and stable technological support for early turquoise mining in the Hexi Corridor, highlighting regional technological interactions before the Silk Road.