Copper and lead are carried in on back for attendant (9)
I believe the answer is:
cupbearer
'for attendant' is the definition.
(cupbearer is a kind of attendant)
'copper and lead are carried in on back' is the wordplay.
'copper' becomes 'cu' (chemical symbol).
'and' says to put letters next to each other.
'lead' becomes 'Pb' (Pb is the chemical symbol for lead).
'carried in' means one lot of letters goes inside another.
'on back' becomes 'er' (I can't explain this - if you can you should give a lot more credence to this answer).
'are' put inside 'er' is 'earer'.
'cu'+'pb'+'earer'='CUPBEARER'
Can you help me to learn more?
(Another definition for cupbearer that I've seen is " Hebe, perhaps".)