This is an old Oracle headgear used on very special occasions by the person usually a monk whose body is inhabited by Lha (spirit of a high demi-God). After the body has been possessed by the spirit, he/she goes into trance and speaks pure Tibetan language and they prophesize about the future.
This is silver engraved with a skull and some kind of leaves on it. Only very few monks get a chance to be an Oracle. They have to meditate for a month before and stay very clean to get possessed. There are semi-precious stones embedded on it, like turquoise and coral.
Age- 60-80 years old