Porcelain container ?

I don't know really anything about but I inherited from my grandparents about 35 years ago...  It's porcelain and in absolutely perfect condition.  It has hallmarks on the bottom that a very hard to read unless your a trained professional...  However I seen one on the antiques roadshow a number of years ago and it was green instead of blue and it was appraised for $2,500.   If anyone knows anything about it please let me know and if your interested im open for offers....  Thank you very much