Church made by graduate with quartz (8)
I believe the answer is:
basilica
'church' is the definition.
(type of large church)
'graduate with quartz' is the wordplay.
'graduate' becomes 'BA' (someone with a Bachelor of Arts degree).
'with' is a charade indicator (letters next to each other).
'quartz' becomes 'silica' (I've seen this in another clue).
'ba'+'silica'='BASILICA'
'made by' acts as a link.
(Other definitions for basilica that I've seen before include "Roman building used for public administration" , "Magnificent church" , "Important church, like St Peter's in Rome" , "Roman style of building" , "Important Roman Catholic church" .)