This stone ax comes from Mount Hagen area, a high plateau in the western highlands of Papua New Guinea. It is a ceremonial axe, a type of axe used mainly as store of wealth and at important rituals.
In the Mount Hagen area, such special axes are the unit of exchange for the bride price up to this day. That payment usually comprises three or four bride price axes, plus a number of ceremonial axes. Only axes used as every-day tools are never used to pay the bride-price. These are not made from stone any more today, but from steel.