Untaxed dealings in coal or jet? (5,7)
I believe the answer is:
black economy
'untaxed dealings in coal' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'jet?' is the wordplay.
I cannot quite see how this works, but
'jet?' could be 'black' ('black' can be similar in meaning to 'jet') and 'black' is located in the answer.
The remaining letters 'economy' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'or' acts as a link.
Can you help me to learn more?
(Other definitions for black economy that I've seen before include "Unrecorded and untaxed dealings" , "Tax-free zone" , "It produces illegally undeclared income" , "A nation's illegally undeclared income" , "untaxed zone" .)