Elongated masks such as this were worn by religious and judiciary members who were members of a secret society called Ngil. They hunted and punished sorcerers, evil doers, those who broke the law and as a mediator between clans and rival villages. Judgment would be passed in magic ceremonies where masks were worn.
Typically, masks were worn by the Ngil when judgment was being passed . . . for an added dramatic effect. The masks were typically elongated, covered with kaolin (soft white clay) and accented with a dark border and dark accents (such as the nose on this one).
As simple as this mask looks, it is linked with death . . . a typical sentence passed down to accused sorcerers.
Age unknown but certainly not recent. Stand not included.