A Chrysanthemum-Lobed Chinese Bowl with Grey Crackle Glaze: Portable X-Ray Fluorescence Characterization and Archaeometric Comparison with Southern Song–Yuan Guan and Ge Wares

A Chrysanthemum-Lobed Chinese Bowl with Grey Crackle Glaze: Portable X-Ray Fluorescence Characterization and Archaeometric Comparison with Southern Song–Yuan Guan and Ge Wares Nona DronovaIndependent Researcher2026 Research Article | Chinese Ceramics | Archaeometry | Non-Destructive Analysis Abstract This study presents a non-destructive examination of a chrysanthemum-lobed Chinese ceramic bowl distinguished by a smooth grey to grey-blue crackle glaze and a narrow, dark, unglazed band around its annular foot. The investigation combines macroscopic photographic documentation, visual analysis of glaze morphology, and portable X-ray fluorescence (pXRF) measurements with a comparative review of published archaeometric research on Southern Song and Yuan dynasty Guan and Ge ceramic traditions. The pXRF analysis of the grey glaze recorded silicon at 38.46 wt%, calcium at 6.954 wt%, aluminium at 6.40 wt%, potassium at 4.147 wt%, and iron at 0.404 wt%. The corresponding theoretical oxide equivalents are approximately 82.28 wt% SiO₂, 9.73 wt% CaO, 12.09 wt% Al₂O₃, 5.00 wt% K₂O, and 0.58 wt% Fe₂O₃. These equivalents represent separate stoichiometric conversions of reported elemental concentrations, not a normalized bulk-glaze composition. The combination of substantial calcium, relatively low iron, a smooth grey-blue surface, a prominent polygonal crackle network, and a contrasting dark foot establishes a meaningful technological and morphological relationship with Chinese crackle-glazed celadon traditions, particularly those associated with Guan and Ge wares. Comparative archaeological research from the Laohudong and Jiaotanxia kiln sites provides an important framework for interpreting the observed glaze chemistry and appearance. The present study contributes an independently documented analytical record of a chrysanthemum-lobed vessel and identifies specific chemical and technological features for future comparative investigation. Keywords: Chinese ceramics; chrysanthemum-lobed bowl; Guan ware; Ge ware; Southern Song; Yuan dynasty; crackle glaze; celadon; portable X-ray fluorescence; calcium-rich glaze; Laohudong; Jiaotanxia; ceramic archaeometry. 1. Introduction Chinese celadon ceramics represent one of the most sophisticated achievements in the history of ceramic technology. Among their distinctive features are carefully controlled glaze coloration, smooth or jade-like surfaces, deliberately emphasized crackle patterns, and contrasting exposed ceramic bodies. The Guan ceramic tradition of the Southern Song dynasty (1127–1279) is particularly associated with refined grey-green and blue-green glazes, complex glaze microstructures, and characteristic crackle networks. The subsequent development and adaptation of related technologies during the Yuan dynasty (1279–1368) contributed to the broader family of ceramics conventionally described as Guan- and Ge-type wares. The present research examines a chrysanthemum-lobed ceramic bowl designated Sample No. 7. The vessel is distinguished by a pale grey-blue glaze, a pronounced network of irregular cracks, and a narrow, almost black, unglazed annular foot. The primary objective is to document its surface chemistry and determine how the observed composition and morphology compare with published studies of historical Chinese crackle-glazed ceramics. This investigation is significant because it combines original non-destructive elemental measurements with a focused comparative analysis of archaeological materials and published explanations of glaze color, opacity, and cracking. 2. Description of the Investigated Bowl 2.1. Vessel morphology The investigated object is a ceramic bowl with a lobed contour resembling the petals of a chrysanthemum. Its exterior displays gently articulated lobes that create a rhythmic floral profile. The vessel rests on a circular foot ring, within which the glaze continues across the recessed base. The combination of floral shaping and a compact annular foot gives the vessel a carefully balanced appearance. 2.2. Glaze appearance The glaze is smooth and glossy, with a soft grey to grey-blue coloration. Under reflected light, its surface displays a subtle luminous quality reminiscent of the jade-like appearance frequently discussed in studies of historical Chinese celadons. A network of intersecting cracks covers the visible glazed surface. The cracks form irregular polygonal fields of varying dimensions. The network continues across the recessed base inside the foot ring, demonstrating that crackle is an extensive characteristic of the glazed surface rather than an isolated decorative feature. The visible crack pattern is consistent with a crazed glaze surface, in which cracks can develop through thermal-expansion mismatch and associated stresses between glaze and ceramic body. 2.3. Dark annular foot A particularly notable feature is the narrow dark band surrounding the edge of the annular foot. This band appears dark brown to almost black and contrasts sharply with the pale grey glaze. Its appearance invites comparison with the historically recognized dark-foot characteristic of some Guan-type ceramics, often discussed under the Chinese expression zi kou tie zu (紫口鐵足), meaning “purple mouth and iron foot.” However, the band was too narrow to be reliably measured with the available portable XRF instrument. Consequently, its elemental composition is not reported in this study. The dark color is documented as a visual feature, not as direct chemical evidence of an iron-rich body. 3. Materials and Methods 3.1. Investigated specimen The object was recorded as: Sample ID: 7 Project designation: tarelka seraya (“grey plate”) Object identification: Chrysanthemum-lobed ceramic bowl Analyzed area: Grey glazed surface The original instrument designation is preserved as part of the analytical record, while the vessel is identified morphologically as a bowl. 3.2. Portable X-ray fluorescence The elemental composition was measured by portable X-ray fluorescence spectroscopy. Instrument and analytical information: Parameter Recorded value Instrument serial number 940487 Analytical method Geochem (3-Beam) Extra Date 28 October 2026 Measurement time 14:18:40 Daily measurement ID 13 Acquisition duration 45 seconds Sample ID 7 Measurement type In situ Measurement area Grey glaze The analytical report presents elemental concentrations and associated instrumental uncertainties. The measurement is treated as a surface-sensitive, non-destructive compositional observation. Because pXRF samples an interaction volume influenced by surface geometry, glaze thickness, and substrate composition, the reported values are not automatically equivalent to the composition of an isolated glaze layer. 3.3. Optical documentation Macroscopic photographs were examined to characterize: The chrysanthemum-like lobed form. The grey-blue glaze coloration and gloss. The morphology and distribution of crackle. The dark exposed annular foot. The continuation of the glaze and crackle inside the recessed base. No microscopic phase identification was performed in the present investigation. 3.4. Oxide-equivalent calculations For comparison with ceramic-science literature, selected elemental concentrations were converted into theoretical oxide equivalents using stoichiometric conversion factors. These calculations are intended to assist compositional interpretation. They are not independently measured oxide concentrations, and their sum must not be interpreted as a normalized glaze recipe. 4. Experimental Results 4.1. Elemental composition of the grey glaze Table 1. Portable XRF results for Sample No. 7. Element Concentration Silicon (Si) 38.46 wt% Aluminium (Al) 6.40 wt% Calcium (Ca) 6.954 wt% Potassium (K) 4.147 wt% Magnesium (Mg) 8,400 ppm Iron (Fe) 4,040 ppm Manganese (Mn) 629 ppm Rubidium (Rb) 572 ppm Strontium (Sr) 121 ppm Barium (Ba) 350 ppm Phosphorus (P) 200 ppm Sulfur (S) 4,330 ppm Chromium (Cr) 77 ppm Nickel (Ni) 35 ppm Copper (Cu) 67 ppm Zinc (Zn) 11 ppm Yttrium (Y) 13 ppm Zirconium (Zr) 60 ppm Niobium (Nb) 48 ppm Iron was reported as 4,040 ppm, equivalent to 0.404 wt%. Titanium was below the reported detection threshold of 190 ppm. Cobalt was not detected above 53 ppm. Arsenic was not detected above 6 ppm. The analytical record did not provide a quantified lead concentration. 4.2. Theoretical oxide equivalents Table 2. Selected theoretical oxide equivalents calculated from the pXRF elemental results. Oxide Calculated equivalent SiO₂ 82.28 wt% Al₂O₃ 12.09 wt% CaO 9.73 wt% K₂O 5.00 wt% Fe₂O₃ 0.58 wt% MgO 1.39 wt% MnO 0.081 wt% Note: These are independent oxide-equivalent conversions of elemental readings. They are not normalized to 100%, and the unusually high combined total demonstrates why they must not be treated as a complete bulk-glaze oxide analysis. 4.3. Chemical characteristics Three features of the elemental results are particularly informative. First, the grey surface contains a substantial calcium signal, indicating an important calcium-bearing component in the analyzed ceramic surface. Second, the iron concentration is relatively low compared with that commonly encountered in dark iron-rich ceramic glazes. Third, the surface contains measurable potassium, aluminium, magnesium, and minor trace elements, providing a multielement dataset for comparison with published Chinese glaze systems. The combination is compatible with a calcium-bearing silicate glaze tradition, although a complete glaze formulation cannot be reconstructed from the present pXRF measurement alone. 5. Comparative Archaeometry: Southern Song and Yuan Guan and Ge Traditions 5.1. Archaeological context The Laohudong and Jiaotanxia kiln sites in Hangzhou occupy a central position in research on Southern Song Guan ceramics.