Query: What color was the famous valley during the Neolithic through to the Shang period?
Context: However, because these marks occur singly, without any implied context, and are made crudely and simply, Qiu Xigui concluded that "we do not have any basis for stating that these constituted writing nor is there reason to conclude that they were ancestral to Shang dynasty Chinese characters." They do however demonstrate a history of sign use in the Yellow River valley during the Neolithic through to the Shang period.