Does anyone know what this coat of arms is?

I have this plate but have no idea what the coat of arms is. Any ideas or info on it would be appreciated

 

Obviously British with the Lion and Unicorn supporters, the coronet is that of a Marquis, essentially a French title but there are some English titles such as the Marquis of Bath.
Lack of a motto makes it a lot harder to pin down. It may be a simple fantasy, it does look rather large, to the extent of vulgarity. Vulgarity, oddly, brings me back to the Marquis of Bath.

Either the backstamp is blurred or the picture is.

 

You can try the easy way by using the Library of Congress Local History and Genealogy webpage "ask a librarian" button. Or the hard way-translate the COA into the language of heraldese and Google the result.

 

It looks like a Cauldon blank sold by a store in Paris called Au Vase Etrusque. Things made esp. for stores are sometimes impossible to ID.

 

Is this a Cauldon plate imported by a Parisian retailer?

Six similar, but not identical, ones for sale on ebay, maybe suggesting Cauldon and a french retailer had got together to offer customised dinnerware for French nobility?

http://www.ebay.co.uk/itm/Rare-6-pl...t-of-arms-1868-crown-of-marquis-/231277249892

 

They are very lovely, but, while I will happily adopt various monograms on silver, I draw the line at coats of arms.

Seems an odd sort of plate to be imported to Paris and ? back again?