Fengshan county of Guangxi Zhuang Autonomous Region boasts the most fully developed large-sized karst halls and dripstone sediments in China, said Zhang Yuanhai, a senior engineer with the institute of karst geology at the Chinese Academy of Geological Sciences.

Zhang made the statement at a recent press conference for the fourth China-Italy joint exploration of karst grottoes in Fengshan county from Dec.23, 2003 to Jan.3, 2004.

Led by Dr. Ruggieri Rosario, the investigation group from the Sicily hydrogeology research center cooperated with experts from the Committee on Speleology of the Geological Society of China to make this scientific exploration.

"Among the 10 largest grottos in China, four are from Fengshan county," Zhang said.

Rosario said karst halls in Fengshan county were much larger than those in Brazil, which is of great significance not only for tourism but also for scientific research.

According to Zhang, the area of two halls of a large karst grotto in Poxin village of Fengshan county were respectively 37,000 and 31,000 square meters, listing the seventh and the eighth largest in China.

"Grottoes in Fengshan county boast more grotto shapes than many famous grottoes in other places, including shapes of halls, corridors, vertical shafts and gorges," said Zhang.

According to Zhang, two important discoveries were made in this exploration.

"We have discovered a big stalagmite, the height of which reaches 36.2 meters, the second tallest in the world, the tallest is 38.2 meters in Slovenia," Zhang said.

The team also found a big stone pearl. As the crystallized product of calcium carbonate, the stone pearl usually forms in shallow water in karst grottos.

The diameter of the big stone pearl reaches 22 centimeters, the biggest in the world as the ordinary diameter is usually one to three centimeter, said Zhang.

Rosario said within 90 minutes he had seen among the subterranean-stream karst grottos in Poxin village nearly all kinds of karst sights, such as vertical shafts, stone forests, subterranean rivers, karst halls and stalactites.

(People's Daily January 12, 2004)