Making allegation about copper in rustic casing (8)
I believe the answer is:
accusing
'making allegation' is the definition.
'accusing' can be an answer for 'allegation' (thesaurus). I am not sure about the 'making' bit.
'about copper in rustic casing' is the wordplay.
I cannot really see how this works, but
'about' could be 'c' (abbreviation for 'circa') and 'c' is located in the answer.
'copper' could be 'cu' (chemical symbol) and 'cu' is present in the answer.
'in' is present in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for accusing that I've seen before include "Indicting" , "Levelling a charge against" , "Charging (someone with crime)" , "Charging with an offence" .)