Cauldon England "Humorous Fox Hunting" Series Plates Question
I have a set of Caulden plates (18 in total. They are marked simply (Caulden England) and have various impressions on the back. All are marked in black with the number of the series (1 -18) and have a number which I assume to be a pattern number of 6243 or 6293. They are also marked with an 7 or an x. One of the plates is slightly different - marked Cauldon England - in blue - and appears to be slightly different in size...Perhaps a little thicker.
Can anyone date these plates for me and explain why the one plate #13 in the series is slightly different?