Chinese archeologists have found alarge ancient saltpeter manufacturing base which they believe was used to manufacture gunpowder over 1,000 years ago.
A team of archaeologists discovered last month a network of caves at the Laojun Mountain in southwestern China's Sichuan Province.
Xu Xiangdong, leader of the expedition and former president of the Beijing Ancient Building Museum, said the caves were used to manufacture saltpeter, one of the major ingredients of gunpowder.
In two caves, the remains of workshops and storage pits were discovered, while in another cave the team found four work spaces,each covering hundreds of square meters, along with several saltpeter pits, and scattered fragments of chinaware.
Based on the finds, scientists estimated the ancient miners could have extracted one kg of saltpeter from 100 kg of earth and the kitchens could have fed 100 workers.
The finds proved that the Laojun Mountain was the largest base for saltpeter production, said the experts.
They speculated that the saltpeter, named "Chinese Snow" by foreigners, was probably transported from here to Europe and west Asia via the road twisting between Sichuan and Gansu provinces.
Experts agreed that the large number of halls in towns and cities around the area were used to trade saltpeter in ancient times.
Gunpowder is one of the four great inventions in ancient China along with paper, printing and the compass.
According to historic records, ancient Chinese found that the mixture of saltpeter, sulfur and carbon was explosive, which led to the invention of gunpowder sometime before the Tang Dynasty (618-907).
However, even today, the history of gunpowder manufacturing still rests on fragments in the historic record.
The manufacture of saltpeter has remained a mystery to Chinese scientists, said Xu Xiangdong.
"We are so excited to find important material proofs regarding the invention of gunpowder," said Luo Zhewen, head of the expert team under the State Bureau of Cultural Relics.
If the Laojun Mountain proves to be the birthplace of gunpowderand the largest exploitation base for saltpeter in history, it will be one of the most significant archaeological discoveries both in China and the world, Xu Xiangdong said.