This is one end of a ring bezel with an impressed design. A portion of the shank is attached.
From Egypt, Giza, Street G 7200, debris E of mastaba G 7210-7220: G 7220. 1924: excavated by the Harvard University–Museum of Fine Arts Expedition; assigned to the MFA in the division of finds by the government of Egypt.
Harvard University—Boston Museum of Fine Arts Expedition