OK !! I have checked all lists,,and everywhere for this mark and it is not a known mark !! It simply does not exist as far as I can find as a pottery !! Not in the U.S. or Europe or the UK !! The crown is not one that would be drawn like that in any of these countries !! Also checked China and Japan and nothing there as well !! That however does not mean it didn`t come from China !! I looked at several with the same mark and all were the same pitcher and bowl with different paint colors !! Often what is found with similar items is that they are Chinese imports !! They have been known to use marks not associated with the pottery that made them just to make them seem better quality than they are !! Another point is the less than quality art work on all these basin sets !! Just a spray on with little hand work says that they were done in a hurry !! I think these were made around mid century as an export item !! I would say China is the most likely country of origin !! They would have had a stick on label stating such !! These are usually removed by whoever buys them !!