This is a rounded sculptural fragment of a limb. It is polished on one half. The stone is black granodiorite with small evenly distributed white and black biotite inclusions (may be diorite). GD3.
From Nubia (Sudan), Kerma, K X grave 1026 no.5. 1913: 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