This is a corner piece of a square object. The back is flat and there is a raised rim around the edge of the top side. There is also an arc-shaped line in raised relief. The object is encrusted in mud. It is incorrectly listed as a shawabty fragment in the Object Register.
From Nubia (Sudan) Gebel Barkal B 501. 1920: excavated by the Harvard University-Museum of Fine Arts Expedition; assigned to the MFA by the government of the Sudan.
Harvard University—Boston Museum of Fine Arts Expedition