Arrange room with centre of column in gold leaf (6)
I believe the answer is:
ormolu
'gold leaf' is the definition.
(I've seen this before)
'arrange room with centre of column' is the wordplay.
'arrange' indicates an anagram.
'with' says to put letters next to each other.
'centre of' says to take the centre.
The centre of 'column' is 'lu'.
'room' is an anagram of 'ormo'.
'ormo'+'lu'='ORMOLU'
'in' acts as a link.
(Other definitions for ormolu that I've seen before include "Gold-coloured alloy used to decorate furniture" , "Gold effect" , "Alloy of copper and zinc" , "Furniture-decorating alloy" , "Decorative gilt alloy" .)