Is it possible to kasher fine china dishes that may possibly have been used for both milk and meat by a previous user? If so, they would now be used only for milk. What is the procedure to kasher these dishes (if it is possible)? Thank you.

Shulchan Aruch Orach Chayim 451:1 writes that china or porcelane dishes that were used to serve hot meals - one cannot Kasher them. Shut Igrot Moshe writes: a porcelane dishes set which is very expensive and it is a great loss to throw them out, may be Kashered only after 12 months of not using them - by cleaning them and dipping each dish three times into boiling water. Rabbi Ro'i Margalit