This elaborately-decorated incised object was found in the Three Gorges area (Wu Shan). The museum label calls it a "support base" (zhi zuo), without further elaboration. Given its bent shape, it's not clear what it could have supported. Probably it started out as an upright pedestal, but accidentally deformed when the soft clay was fired.
The Late Neolithic in China lasted from approximately 5000 BC - 2000 BC.