was there someone from the royal family or anyone who utilized this piece?
Charles VI of France
Royal Gold Cup
There is no firm evidence as to the date and circumstances of the creation of the cup. It is first clearly documented in an inventory from 1391 of the valuables belonging to Charles VI of France (reigned 1380–1422), surviving in two copies in the Bibliothèque nationale de France. 
what is royal gold cup? It is a solid gold covered cup lavishly decorated with enamel and pearls. is it kept in a museum? Yes, in the British Museum who designed it? John, Duke of Berry
wiki:689917
Royal Gold Cup [SEP] Provenance
For some reason it does not appear in a royal inventory of 1441; Jenny Stratford suggests that this was because Beaufort still had it at this point. Another possibility is that it had been pawned, as it was in 1449 and again in 1451, on both occasions to finance England's to hold on to French territory;