From the Wikipedia page 
Jiahu symbols (Chinese: 賈湖契刻符號; pinyin: Jiǎhú qìkè fúhào) refer to the 16 distinct markings on prehistoric artifacts found in Jiahu , a neolithic Peiligang culture site found in Henan, China, and excavated in 1999. The Jiahu site dates to 6600 BC; some archaeologists believe the markings to be similar (although without necessarily having the same meaning) to some characters used in a much later writing system related to the oracle bone script (e.g. similar markings of 目 “eye”, 日 “sun; day”), but there is currently no consensus. A 2003 report in Archaeology interpreted them "not as writing itself, but as features of a lengthy period of sign-use which led eventually to a fully-fledged system of writing." The earliest evidence for a corpus of writing in the oracle bone script dates much later to the Shang Dynasty (c. 1600 – 1046 BC).