Is it possible for modern reproductions to also have that burnt orange or rust color on their bases. The presence of burnt orange or rust color is a nice Ming feature when it is there and the piece is ok anyway, but the practical use of looking for this feature is more or less limited to distinguishing between Chinese and Japanese porcelain, since the Japanese clay does not have enough iron content to burn orange. It might also be helpful while determining if a piece really is Ming or a Qing or later copy. But it will take some experience before you can really make something out of this, I am sorry to say. This information is given as an example of private conversation only and is not intended to be used as a promotion of any individual piece.
All opinions is the authors and is given as such with all hazards of judgeing anything from a photo.