This is a fragment of a pendant; possibly a pendant bead.
From Giza, Menkaura Pyramid Temple, room J2 (= sloping corridor 28). 1907: excavated by the Harvard University–Boston Museum of Fine Arts Expedition; assigned to the MFA in the division of finds by the government of Egypt. (Accession date: March 2, 1911)
Harvard University—Boston Museum of Fine Arts Expedition