Since slate is not found in the Peinan area, it is believed the material was brought from the Central Mountain Range of Taiwan. If this is the case, then the people of the time must have had some fairly advanced form of transportation. The slate, however, crumbles so easily that few of the human remains are preserved.
石棺用的板岩，非當地所產，一般推測是從中央山脈運下來的，因而當時的搬運工具可能已很進步，但板岩容易風化，所以骨頭的保存也較不完整。