A
hand axe is a
prehistoric stone tool with two faces that is the longest-used
tool in
human history. It is usually composed of
flint or
chert. It is characteristic of the lower
Acheulean and middle
Palaeolithic (
Mousterian) periods. Its technical name (biface) comes from the fact that the archetypical model is a generally bifacial
Lithic flake with an
almond-shaped (amygdaloidal) morphology. Hand axes tend to be
symmetrical along their longitudinal
axis and formed by pressure or percussion. The most common hand axes have a pointed end and rounded base, which gives them their characteristic shape, and both faces have been
knapped to remove the natural cortex, at least partially. Hand axes are a type of the somewhat wider
biface group of two-faced tools or weapons.