Bifacial knife made by hard and soft hammer percussion

The ‘Stone Flaking Techniques’ video series by the Museum of Stone Tools demonstrate some of the flaking techniques that were used to make tools from the origins of the technology, ca. 3.3 million years ago, to the recent past. The techniques are demonstrated by Professor Mark Moore, Museum Director and archaeologist at the University of New England in Australia. In this video, a nodule of Australian flint is reduced into a bifacial knife using hammerstones, antler hammers referred to as ‘billets’, and antler pressure flakers. Bifacial knives similar to arose independently from the Palaeolithic to the Neolithic and metal ages, and in many parts of the world, including Europe and Western Asia, North America, and Mesoamerica. The video begins by showing hard-hammer percussion flaking to establish a bifacial edge around much of the nodule. Next you see the reduction of the bifacial blank with antler billets of various sizes. The shape of the knife is achieved simultaneously with thinning. In the later stages, some of the platforms are isolated by pressure flaking. The final step was to remove edge irregularities and ‘deltas’ between flake scars using antler pressure flakers. The stone flaked in the video is unheated Australian flint from southeastern Australia. Whole-rock testing has shown that this Australian flint is 88.7% silica, compared to flints from other parts of the world, which average 96.5% silica and range up to 98.1% silica. The Australian flint ranks just above mudstone, at 84.0% silica, and silicified volcanic ash, at 83.8% silica. It has the same workability as coarse chert (about 4.0 on Callahan’s lithic grade scale).