Flash, sparkle (9)
I believe the answer is:
coruscate
I believe this clue is a double definition.
'flash' is the first definition.
(thesaurus)
'sparkle' is the second definition.
(I know that sparkle can be written as coruscate)
(Other definitions for coruscate that I've seen before include "Show flashes of brilliance" , "Flash, sparkle" , "Glitter or sparkle in court case" , "Shimmer and flash in court case" .)