This is a string of 63 blue faience ball beads with a pendant composed of a of natural quartz crystal glazed blue. The glazing of quartz crystals was practice unique to Kerma, where the crystals may have been believed to have magical or amuletic powers.
From Nubia (Sudan) Kerma: K10 B-61. March, 1914: Excavated by the Harvard University-Museum of Fine Arts Expedition; assigned to the MFA in the division of finds by the government of the Sudan. (Accession date: March 1, 1920)
Harvard University—Boston Museum of Fine Arts Expedition
Nubian, Classic Kerma, 1700–1550 B.C.