Porcelain appeared in China in the early Christian period. It was made from an exceptionally white clay called kaolin. Europeans were fascinated by porcelain and would spend centuries trying to find the secret of this ceramic which was translucent, brilliant and sonorous. Its name comes from the Italian wordporcellana, a white, polished shell which was believed to form part of the composition of this mysterious material. Chinese porcelain was exported to Europe from the 16th century. The development of shipping routes and the creation of the Dutch East India Company favoured trade in precious ceramics largely destined for export or commissioned by Occidental clients. The success was such that the town of Jingdezhen, the main centre for production in China, became a protected city and forbidden to foreigners in order to protect production secrets. Japan produced porcelain from the early 17th century in Arita. The Japanese Imari decorative style was highly popular in the 18th century and imitated simultaneously in Europe and China.