nDepolishing(Ceramics) The process of removing the vitreous glaze from porcelain, leaving the dull luster of the surface of ivory porcelain.
Century Dictionary and Cyclopedia
ndepolishingThe process of removing polish or glaze; specifically, in ceramics, a process whereby the glaze on ware is removed. Ware with the resulting dull surface is called ivory porcelain. It corresponds to the deglazing of glass.
We can, however, go far beyond the mere depolishing of glass; indeed I have already said that quartz-sand can wear a hole through corundum.