Thank you so much for coming back to us, and uploading these photos. They're perfect, and very helpful.
As you probably know, you have two collectors' plates here from a series produced by Coalport in the 1980s which they called "The Tale of a Country Village". There were twelve plates in the series, including The Village Green, The Wedding, The Village Shop, The Windmill, The Farmyard, The Old Mill Stream, Harvest Time, Village School, The Village Smithy, Picnic by the River, and the two that you have, Granny's Cottage and The Old Mill.
The front of each plate carried a design based upon an original painting by Robert Hersey. The series was commissioned and distributed by The Danbury Mint, and you can see their monogram near the middle of the backstamp. The company specialises in developing and promoting collectors' series in ceramics, glass and resin, as well as jewellery, stuffed toys and figurines. "The Tale of a Country Village" series of collectors' plates was issued over a period of almost two years in the late 1980s, and was completed in 1989. They were issued to subscribers, and came in a special box, complete with certificate of authenticity.
Robert Hersey is still very active, and is currently a senior lecturer in Fine Art and Painting at the University of Brighton, in southern England.
That's all the interesting background, but the regrettable fact is, these plates have not proven to be an investment. They are worth less now than collectors paid for them in 1989. Indeed, the market generally for so-called "Collectors Plates" has collapsed in recent years, for two reasons., Firstly, companies like Danbury Mint released far too many sets, and each set, although technically a "limited edition", was issued by the several thousand. Secondly, tastes have changed, and there simply aren't as many collectors for plates like these as there used to be. Consequently, prices are not encouraging, and it is possible to find a complete set of 12 plates from this series being sold for around $60 - $70, but occasionally less. Single plates fetch $8 - $10 each. Those still in their original box, with certificate, command the higher prices.
As with all ceramics, condition is key, and to achieve a top-end price, the piece must be as-new, without any chips, cracks or crazing to the glaze, and with no visible wear to the surface.
I'm sure you were hoping for something better, but I hope this is still helpful. If there's anything else you'd like to know, please ask. If you feel I have resolved your question satisfactorily, please rate my answer by selecting the number of stars (top right on your panel) that you think I deserve, and clicking the "Submit" button. This will complete the question ... although you can still add more comments if you wish.