In France I get discontented wife large gemstone (5)
I believe the answer is:
jewel
'gemstone' is the definition.
(I know that gemstone can be written as jewel)
'in france i get discontented wife large' is the wordplay.
'in france i' becomes 'je' ('I' in French).
'get' means one lot of letters go next to another.
'discontented' suggests removing the centre (the word's contents are removed).
'large' becomes 'L' (eg in clothes sizes).
'wife' with its middle removed is 'we'.
'je'+'we'+'l'='JEWEL'
(Other definitions for jewel that I've seen before include "Precious stone or mineral" , "Gemstone" , "Gem" , "eg Ruby" , "(Semi) precious stone" .)