A typology was established for 15 pottery artefacts at Chejuisland. Conjectured methods of manufacture were confirmed by radiography X-ray diffraction. Scanning electron microscopy etc. The compositions and mineralogy of $500^{circ}C$ to $1200^{circ}C$ was measured and compared with those of microstructure. The mechanism of sintering was impurity-initiated, liquid-phase sintering. The making, firing, and sometimes exploding of the figurines may have been the prime function of the pottery at this site rather than being manufactured as permanent, portable object.