Between 1039 and 1048 CE, artisan Bi Sheng invented movable type printing during China's Northern Song dynasty. His system used individually fired ceramic characters arranged on an iron plate coated with resin, wax, and paper ash. Multiple copies of common characters allowed for efficient typesetting. The invention was documented by scholar-official Shen Kuo in his Dream Pool Essays (1088). Ceramic movable type continued in use in China through the Qing dynasty.