An important Eskimo polychrome wood mask will auction on May 21 at Sotheby's New York.
The piece, valued at $350,000-550,000, will headline the Arts of the American West sale - which includes a range of artefacts created by Native Americans.
It is thought to have been crafted by the Yupik or Anvik peoples of western Alaska and was formerly held in the collection of surrealist painter and sculptor Enrico Donati.
The mask would once have featured eye frames and fur trim around the edges, although these have since been lost. In place of a mouth are two holes similar in form to the nostrils of a seal.
In December last year, a walrus ivory head consigned by the Yupik made $197,000 at Bonhams.
A Comanche hide shield is offered with an estimate of $300,000-450,000.
The piece is thought to date to the mid 19th century and would have been used in hand-to-hand combat.
The design features a grizzly bear, sun and mountain and relates to an early creation myth. Two similar examples feature in the collection of the United States National Museum in Washington, DC.
Other important lots in the sale include a Kwakiutl polychromed wood transformation mask, which carries an estimate of $200,000-300,000.
We have this authentic strand of hair from the legendary Apache leader Geronimo.
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