MIJIAYA, CHINA—A new study shows that ceramic pots and funnels unearthed at a Neolithic site in Shaanxi province were used in China's earliest known brewery. Stanford University archaeologist Jiajing Wang analyzed residues on the artifacts, which date to between 3400 and 2900 B.C. and found traces of the chemical compound oxalate, a byproduct of brewing beer. She also discovered residues left by grains, including barley, which came as a surprise to her, since the earliest barley thus far known in China has been found in Bronze Age sites dating to around 2000 B.C. The grain was first used by the ancient Mesopotamians for brewing beer. "It is possible that when barley was introduced from western Eurasia into the Central Plain of China, it came with the knowledge that the grain was a good ingredient for beer brewing," Wang told Live Science. "So it was not only the introduction of a new crop, but also the knowledge associated with the crop." To read more about archaeology in China, go to "Tomb Raider Chronicles."