Large Blue Delft Plate Charger

 Has french tag on back, put there by previous owner, who was a collector, and traveled. I am unable to translate it though. I was told she tagged everything with where she found it and any info she knew about the item. Also I have found this plate design on one other delft plate online, but the stamp on the back is different than mine. I would like to know what the item is worth. If anyone knows anything about the writing on the back, and possibly the era of the plate. I am quite attached to it, and would love to know more about it.

Good