The reverse of material extracted from the earth (5)
I believe the answer is:
mined
'extracted from the earth' is the definition.
I can't tell whether this definition defines the answer.
'the reverse of material' is the wordplay.
'the reverse of' shows that the letters should be reversed in order.
'material' becomes 'denim' (type of fabric).
'denim' written backwards gives 'MINED'.
Can you help me to learn more?
(Other definitions for mined that I've seen before include "proceeded secretly" , "Sought diamonds?" , "laid eggs" , "Excavated as for coal or diamonds" , "Dug from pit" .)