First, on the basis of Delft's experience with red stoneware, he improved the kiln design to produce a higher firing temperature and made a hard red stoneware similar to Yixing ware. But sadly this still fell some way short of the pure white porcelain which the elector craved after day and night.
他先就德爾福特朱泥硬陶的經驗，改進窯的構造，調出更高的溫度，燒出了類似宜興質地的紅土器，可惜與皇上朝思暮想的瑩潔白瓷仍有距離。