Q: What I stumbled on while going down a Tumblr rabbit hole was that it is a Tsimshian mask representing the spirit of Upper Air. Supposedly from BC, Canada (19th C.). Hans, 1684
A: Christie’s auctioned this mask last year for over half a million dollars. Obviously it is a very desirable artifact. I did see a similar Tlingit singing shaman’s mask somewhere. The Tsimshian and Tlingit cultures are situated next to each other in Southeast Alaska. There is plenty about their folk art in libraries and the Internet. Enjoy. A+ 
