added by archaeologs Industrial center of the Sukhothai state in northern Thailand with over 600 kilns for pottery and stoneware. The Chalieng brown-glazed wares, Sukhothai black-on-cream wares, and green-glazed Celadon wares are the best known. They are collectively called Sawankhalok and dated to the 14th-16th centuries AD (though have earlier phrases in some places).