I have some plates from John Maddock & Sons I'm curious about.
They are the JEWEL pattern; there is one dinner sized plate and several smaller (salad?) sized plates.
The markings on the back show the company's Crown/Circle marking with the words John Maddock & Sons Ltd Royal Vitreous, England within the circle and the word JEWEL underneath. There is also a small triangle printed on the bottom of the plate as well as a crown imprint in the bottom.
The pattern has a brown border with black and aqua colored scrolling, and a scalloped edge to the plate.
***NOTE: the photos below are borrowed from info I found online (I have not had the chance to upload my own yet).
The first is a good photo of the pattern itself from the website: www.replacements.com
The second shows an example of the imprint on the bottom (mine is identical except it says Jewel underneath) from the website: www.artfire.com