Good ancient arable land fine for valuable cover (4,4)
I believe the answer is:
gold leaf
'valuable cover' is the definition.
'gold leaf' can be an answer for 'cover'. I am not sure about the 'valuable' bit.
'good ancient arable land fine' is the wordplay.
'good' becomes 'g' (abbreviation).
'ancient' becomes 'old' (similar in meaning).
'arable land' becomes 'lea'.
'fine' becomes 'f' (abbreviation in pencil classifications).
'g'+'old'+'lea'+'f'='GOLD-LEAF'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for gold leaf that I've seen before include "Decorative foil" , "Beaten metal for decoration" , "Expensive film" , "Thin metal for gilding" , "Thin metal used as decoration" .)