This is a cryptic definition - the entire clue provides a roundabout or metaphorical way to describe the answer, rather than using wordplay techniques like anagrams or hidden words.
Think about what might be considered a 'golden age' that could occur 'at end of festivities'. Consider what typically happens when celebrations or parties wind down, and what time period might be associated with both luxury and the conclusion of events.
Answer: SIXTISH | This is a cryptic definition where 'Golden age' refers to when people might feel most sophisticated or wealthy (sixtish), and 'at end of festivities' suggests the time when parties typically conclude - around 6 o'clock when formal events often end.