Interested to see if anyone has ever come across this back before as a deck or a single. It is a Congress 606 deck named "Violet" and varies greatly from the known Violet designs listed in the CPCC catalog.
I noticed this back previously in my "Card Games and How to Play Them" booklet c1900 which shows this card listed among several other Congress backs with a gold filigree border.
Separately a small section of this card is also pictured on the front of a "Simple Whist" booklet I have, however the card pictured does not have any border details. I didn't think too much about this beyond wondering if the cards were never produced since no one I talked to (including several prominent Congress deck and wide named singles collectors) had ever seen as much of a single of this back design.
All of that changed when I recently came across a complete 52 card deck in the original box with this design which is now in my collection. It contains a US6c Congress ace of spades but sadly is missing the Joker, which I suspect may have been the "named" picture-type which the other decks of that era would have had.