This old mask is from the Abelam people who live in the East Sepik province of Papua New Guinea. They are a farming society in which giant yams are an especially important food source. The masks are used to decorate harvested yams. Carvings like this (collected more than 40 years ago) were not made with steel tools and are often more beautiful than the more modern versions.
You can see this and many other authentic Abelam and Wosera yam masks from the Dick Jemison Collection at Galerie Mourlot in New York City during Tribal Art Week, May 4-8. Thank you, David Cassera, for reminding us of this important show.