Where are Tenmokus made?

Tenmoku takes its name from the Tianmu Mountain (天目Mandarin: tiān mù; Japanese: ten moku; English: Heaven's Eye) temple in China where iron-glazed bowls were used for tea. The style became widely popular during the Song dynasty.
In Chinese it is called Jian Zhan (建盏), which means "Jian (tea)cup".According to chronicles in 1406, the Yongle Emperor (1360–1424) of the Ming dynasty sent ten Jian ware bowls to the shōgun Ashikaga Yoshimitsu (1358-1408), who ruled during the Muromachi period.
A number of Japanese monks who traveled to monasteries in China also brought pieces back home. As they became valued for tea ceremonies, more pieces were imported from China where they became highly prized goods. Three of these vessels from the southern Song dynasty are so highly valued that they were included by the government in the list of National Treasures of Japan (crafts: others).
The style was eventually produced in Japan as well, where it endures until this day. The Japanese term gradually replaced the original Chinese one for general ware of the type. Of particular renown were the kilns that produced tenmoku are Seto ware.
The glaze is still produced in Japan amongst a very small circle of artists, one being Kamada Kōji (鎌田幸二). Others are Nagae Sōkichi (長江惣吉),Hayashi Kyōsuke (林恭助),and Oketani Yasushi (桶谷寧). Japanese artists have been helping in successfully re-introducing the technique back in China.