Cypro-Minoan syllabary

The Cypro-Minoan syllabary (abbreviated CM) is an undeciphered syllabic script used on the island of Cyprus during the Late Bronze Age (ca. 1550-1050 BC). The term "Cypro-Minoan" was coined by Sir Arthur Evans in 1909 based on its visual similarity to Linear A on Minoan Crete, which CM is thought to be derived from. Approximately 250 objects bearing Cypro-Minoan inscriptions have been found, including clay tablets, votive stands, clay cylinders and clay balls. Discoveries have been made at various sites around Cyprus, as well as the ancient city of Ugarit on the Syrian coast.
The inscriptions have been classified into four closely related groups by Emilia Masson: archaic CM, CM1 (also known as Linear C), CM2 and CM3, although some scholars disagree with this classification. Little is known about how this script originated, or what language was used to write in CM. However, its use continued into the Early Iron Age, forming a link to the Cypriot syllabary, which reads as Greek and has been deciphered.
More information, including recent developments, on the Wikipedia page 
Category:Undeciphered writing systems
Category:Ancient World