LANZHOU, CHINA—According to a Phys.org report, people in northwestern China were systematically using coal some 3,700 years ago, or about 1,200 years earlier than previously thought. An international team of researchers led by Menghan Qiu of Lanzhou University investigated the Bronze Age layers at the site of Jirentaigoukou, and discovered coal in fireplaces, storage pits, homes, smelting furnaces, and near tool caches, suggesting that it had been used to cook food, generate heat, and smelt metal for weapons and tools. The widespread use of coal, which was plentiful at or near the surface of the earth close to the settlement, may have been established as wood became scarcer in the area, the researchers concluded. Read the original scholarly article about this research in Science Advances. To read about bronze smithing in ancient China, go to "(Un)following the Recipe."