In the book 'IJzerwerk van Centraal-Afrika' by H. Westerdijk, I found a drawing of a similar spearhead. This author writes that this type of spear comes from the Nkundu, Loi and/or northern Ntomba living in the central part of Congo. He states that these hooked spears were used for hunting and fishing.
In this region similar shaped arrowheads are found.
Very nice piece
