A piece of porcelain found under the sea has been returned to Central China's Hunan province. [Photo by He Wei/hunan.gov.cn]

A stash of 1,200-year-old Chinese treasure found under the sea has been returned to Central China's Hunan province.

The 162 pieces of treasure were part of a huge cargo of ninth-century porcelain traded from China during the Tang Dynasty (618-907) via an Arab dhow, which wrecked in Indonesia's Java sea. In 1998, a German salvage company discovered the shipwreck and named it "Batu Hitam". More than 67,000 pieces of treasure were found in the ship, 85 percent of which came from a kiln in Changsha, now Hunan's capital city.

Most of the porcelain is now owned by Tilman Walterfang, head of the salvage company. In September, the administration office of the kiln in Changsha signed an agreement with Walterfang to return a collection of 162 pieces to China.

The treasure sent home includes fine ceramics from several kilns in the provinces of Hunan, Zhejiang, Hebei, Henan and Guangdong. Experts believe they will provide evidence of China's overseas porcelain trade during the Tang Dynasty.

The treasure is expected to be accessible to the public at a museum in Changsha in early 2018.