Gigaku are Japan's earliest masks. They were used in Japan for a dance drama (or play without words) as early as 612 AD. Unlike Noh masks which just cover the face, gigaku are larger and cover the whole front of the head. I am grateful to Arie Vos of Kitsune Japanese Art Gallery for identifying this character as Taikofu, a tottering old man.
This mask is hard to date, but I believe the patina, wear and condition date it as late 19th C, or early 20th C.
It, like a Noh mask, has the interior covered in a cloth and impregnated with sizing - the exterior is brown lacquer with black, red, and gold highlights. Measurements are 10-1/4" high x 6-1/2" wide.
There is some damage to the mask. It is structurally sound, but please scrutinize the photos.