Splendid old gold coin (5)
I believe the answer is:
noble
I believe this is a double definition.
'splendid' is the first definition.
(thesaurus)
'old gold coin' is the second definition.
(historical English coin)
(Other definitions for noble that I've seen before include "Worthy" , "Maybe count" , "Stately" , "Illustrious - old money" , "eg Earl" .)