Dawenkou Culture (jan 1, 4500 BC – jan 1, 3000 BC)
Description:
 Group of communities who lived primarily in Shandong. The culture successfully co-existed with the Yangshao culture. Turquoise, jade, ivory artifacts, and the earliest examples of alligator drums are commonly found at Dawenkou sites. Neolithic signs, perhaps related to subsequent scripts, such as those of the Shang Dynasty, have been found on Dawenkou pottery. 
Added to timeline:
Date:
jan 1, 4500 BC
jan 1, 3000 BC
 ~ 1500 years