I have a lot of 3 vintage floral dishes.  They are porcelain.  In the first photo top left the dish is about 6" across the center, in good condition.  Top right has 1 small chip on the top outer edge about the size of a pen tip, it is 6 1/8" across the center, this also shows a slight amount of wear/discoloration on the inside front.  Bottom is about 6 3/4" across the center.  It is in nice condition