what writing system found at minoan sites has not been deciphered
Mycenaean Greek and Linear B. Linear B is the first attested writing system of the Greeks. It was used between the 17th (or 15th century) and 12th century BC and was successor of the Minoan Linear A, a writing system that has not yet been deciphered. Most records have been found on clay tablets in Knosos (Crete), Pylos and Mycenae (Peloponesos) but evidence of its usage reaches as north as Aiani (Macedonia).