Stuff in case emptied out after gold turned up in container (7)
I believe the answer is:
trounce
'stuff' is the definition.
(both can mean to defeat)
I don't understand the remainder of the clue.
(Other definitions for trounce that I've seen before include "Aged skip" , "Beat badly in recount" , "Flog" , "Massacre" , "Beat roundly" .)