Pleading about metal (4)
I believe the answer is:
lead
'metal' is the definition.
(I know that lead is a type of metal)
'pleading about' is the wordplay.
'about' indicates the answer is hidden within the clue (the clue goes around or about the answer).
'LEAD' can be found hidden inside 'pleading'.
(Other definitions for lead that I've seen before include "front man" , "initiative" , "first guitarist" , "Main news story" , "in first place" .)