Clue one composed about power and riches (8)
I believe the answer is:
opulence
'riches' is the definition.
(thesaurus)
'clue one composed about power' is the wordplay.
'composed' indicates anagramming the letters.
'about' indicates putting letters inside.
'power' becomes 'p'.
'clue'+'one'='clueone'
'clueone' is an anagram of 'oulence'.
'oulence' going around 'p' is 'OPULENCE'.
'and' acts as a link.
(Other definitions for opulence that I've seen before include "State of wealth or abundance" , "Conspicuous wealth" , "State of great prosperity" , "Rich quality" , "Wealth, luxury" .)