More than 300 items used by prehistoric people in daily life 4,000 years ago were unearthed in Northwest China's Ningxia Hui Autonomous Region.

Wang Xiaoyang, head of the archaeological team that made the discoveries, said on Monday that the pieces were found at an 800-square-meter excavation area at the Beiyuan relic site.

The artifacts include clay pots, basins, cups and knives, stone axes and chisels, as well as bone awls and needles. Archaeologists also found clamshells which they believe were used for decoration.

The Beiyuan site, which covers 25,000 square meters, was first excavated in 2013. This year about 40 people led by the Ningxia Regional Archaeological Institute conducted a second excavation to learn more about the Neolithic culture and development of the region.

Experts searched 11 houses - one cave dwelling and 10 kivas - 151 pits, three kilns and a tomb. The kivas were square in shape with a round cooking range at the center and were painted white with lime.