Identify this piece...Wedgwood/Jasperware??

Looking to identify this item. It's large and heavy and beautiful! 26 inches diameter. I was told it's a Wedgwood and at least 80 years old. It has a felt backing so I can't see any marks that might be behind the felt. The only mark I see is on the bottom of the front: "RD NO 38497". Any help or information is greatly appreciated!

 

Photos of the back, even with the felt, and a shot of the edge from the side would be helpful.

Interestingly a silverplate platter with the same design and mark sold at auction here...

https://www.ukauctioneers.com/aucti...s=50&sortBy=lotsort&lotView=list&imagesOnly=N

 

Oh wow, thanks for that info. Additional files attached.

 

Unfortunately I think this is a resin casting rather than jasperware.

 

Not Wedgwood, agree with @aaroncab, those tiny bubbles in the side view are a good indicator of a cast piece, e.g. resin or some other plasticized material.

 

https://www.worthpoint.com/worthopedia/incolay-ston-coralay-classics-plaque-12893158

 

The one on Worthpoint sold for $247.50.

 

Brand new from the factory they are currently 750.

http://www.cowboyindian.com/inwd05154.htm

 

Great investigative work!!! Very interesting.

 

Was looking and saying "WOW....they screwed into it???".....then read on.....PHEW!!!!

 

I think maybe it was the purchasers that got screwed ...$750?

 

If it's really Incolay they can go for high prices sometimes. We recently had some discussions about Incolay in another thread. True Incolay is NOT made from resin... Although perhaps they use some substance like that to fuse the minerals? See this info on the same site linked above.
http://www.cowboyindian.com/incolay.htm

Here is our previous discussion. @Bronwen knows about Incolay, and she says here that they do use colorless resin as a binder. (Note, this was in the Laughable eBoo Listings thread and we got off track.) https://www.antiquers.com/threads/laughable-eboo-listings.28501/page-54#post-2419975

 

Knowledge benefits everyone. Thank you so much to everyone for sharing insights and experience!