This is a fragment of a wig with vertical striations and a feathered pattern perpendicular to the wig striations. It may be part of a Queen's headdress. The stone is black granodiorite, the break areas look almost melted (often with large pink feldspar veins or inclusions). GD4.
From Nubia (Sudan), Kerma, K X corridor 9-5. 1914: Excavated by the Harvard University–Boston Museum of Fine Arts Expedition; assigned to the MFA by the government of Sudan.
Harvard University—Boston Museum of Fine Arts Expedition