Phase IV hammerstones are light and have many impact marks.

第四阶段的石锤很轻，且有很多击象。

The stones were then worked into shape using hammerstones and erected using precisely interlocking joints, unseen at any other prehistoric monument.

然后，这些石头被锤石加工成形，并使用精确的交错缝隙竖立起来，这在其他史前遗迹中从未见过。