Qin Dashu, a professor at Peking University's School of Archaeology and Museology, says ceramics achieved predominance in China's exports in the 10th century.

"The products, although not in great quantities, were shipped to as far as the Swahili-speaking areas in eastern Africa," he says.

"They were manufactured at kilns in both northern and southern China to include the most representative types of ceramics of the period."

After leaving Chinese ports, ships headed to connecting ports along the Strait of Malacca. Then the ceramics were transferred to other ships that would sail through the Indian Ocean, along the west bank of the Persian Gulf and into the Gulf of Aden, he adds.

Porcelain exports reached a height in the Southern Song Dynasty (1127-1279), prompted by huge progress in productivity, the craft of boat-building and seamanship. Kilns were built in Jingdezhen, Jiangxi province, and in Zhejiang and Fujian provinces to specifically cater to the rise in overseas orders.