Point

Stone tools where thick chips have been designed into a pyramid shape are referred to as Pyramid Stone Tools. Many have sharp pointed tips but when we look at their sections, we see a rich diversity in shape including triangles and trapezoids. In the northwestern region of Kyushu, we see examples where three sections have been made into a long thin triangular, spearheaded shape. Referred to as Three Sharp Pointed Stone Tools, they are regarded as spearheads for hunting.
This stone tool was discovered at the Imayama ruins in the West Ward of Fukuoka City. It is a large example where an oblong thick stone chip has been worked on. Presently it lacks about 5mm at its tip but remains the largest example when compared to other unearthed items. The material quality is presumed to be glassy andesite.
This stone tool is not an unearthed item but one that was collected. However similar stone tools have been discovered in the upper Aira Tn ash zone (AT). AT is volcanic ash, which fell over a wide area when the Aira Caldera (crater), situated in inner Kagoshima Bay, erupted violently some 26,000 years ago. Because Three Sharp Edged Stone Tools were unearthed above the ash, it is believed that they were created after the violent Aira Caldera eruption some 26,000 years ago.