For example, London wealth (7)
I believe the answer is:
capital
I believe this clue is a double definition.
'for example london' is the first definition.
(London is an example)
'wealth' is the second definition.
(I've seen this before)
(Other definitions for capital that I've seen before include "Most important city" , "Topping" , "Fantastic!" , "Finance - excellent!" , "Major city - investment - excellent" .)