Research on the Composition and Manufacturing Technology of the Single-Eared Octagonal Gold Cup Unearthed from the Turki Mountain Tomb in Inner Mongolia

The Turki Mountain Tomb, one of the three most representative Liao Dynasty tombs, has yielded numerous exquisite gold and silver artifacts during excavation that have drawn global attention for their superb craftsmanship and distinctive ethnic and period characteristics. However, their manufacturing technology had seldom been studied. In this paper, alloy composition analysis and surface microscopic observation were performed on the single-eared octagonal gold cup unearthed from the Turki Mountain Tomb, utilizing portable X-ray fluorescence spectroscopy (p-XRF) and an ultra-depth field microscope. The composition results at different base material locations of the gold cup were similar, with gold content ranging from 84% to 88% and silver content ranging from 10% to 13%. The p-XRF spectra at the exact center of the ring foot, as well as the pearl roundel on the abdominal ridge and rim, showed dominant Au with minor Ag content. Therefore, it could be concluded that the material of the gold cup was made of Au-Ag alloy. Microscopic observation preliminarily revealed that the manufacturing process involved casting, engraving, and welding. The single-eared octagonal gold cup exhibited numerous conspicuous shrinkage cavities, and it was inferred that the gold cup was formed using casting technology. After the cup body, ring foot, and finger pad were cast separately, they were welded together to form the complete gold cup. In addition, green solder and insufficient fusion of welding material were found between the weld seam of the cup body and the ring foot. The exterior surface of the gold cup was adorned with patterns, such as fish-toe circle, upward lotus motif, and pearl roundels. The average diameter of the fish-toe circle was 303 μm. By examining the overlapping conditions of engraving, it could be inferred that the proposed engraving sequence was to engrave the fish-toe circle first, followed by the flower patterns. As a representative of the exquisite artifacts from the Turki Mountain Tomb, the research of the composition and manufacturing technology of the gold cup provides reference data for the scientific analysis of Liao Dynasty gold and silver artifacts.