what a beautiful technique! I have done this quite by accident with pierced low fired earthenware fragrance tart burners, the clear overglaze ran into and filled the pierced decorations. I really was pleasantly surprised with the effect once used when the candlelight shown through softly. No where near the beautifully delicate porcelain work on your link- Wow, will have to keep my eye open and add one to my treasure collection when found. thanks for the link!