Nepalese Buddhist Ritual Mask: "Mahakala"

Mahakala is a deity that protects the land, crops, and people. It also purifies and fights evil. Mahakala is relied upon in all schools of Tibetan Buddhism.

However, he is depicted in a number of variations, each with distinctly different qualities and aspects. This mahakala mask is made from wood and shows the characteristic five skull crown. The five skulls signify victory over the five emotional illusions. His third eye expresses the wisdom of omniscience. The Mahakala character is ever present in ceremonies throughout the Himalayan region. These masks are used to defeat evil spirits and, when not being used for a ceremony, are hung on the walls of Tibetan homes to keep out evil forces.

This kind of mask is used during Tibetan monastic dances called the Cham Dance or Deity Dance, which protects the village and people at the beginning of the year. It is meant to bring protection, positive energy for the whole year. The lama wears the mask high on his head and uses the open mouth as his eye holes. He would be wearing a yak tail mane over his head and a full dress costume.
 
Source:
http://www.masksoftheworld.com/India/Himalaya Mask Tibet Lrg.htm http://www.trocadero.com/pmorse/items/357684/item357684store.html
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