This obsidian amulet takes the form of a headrest. Such amulets were common in Late Period burials, where their magic was intended to lift the head of the deceased at the moment of resurrection.
From Giza, G 7652A, Room IV. April 29, 1929: excavated by the Harvard University-Museum of Fine Arts Expedition; 1929: assigned to the MFA by the government of Egypt.
Harvard University—Boston Museum of Fine Arts Expedition