Bellow's last novel is Glass (7)
I believe the answer is:
crystal
'glass' is the definition.
(crystal is a kind of glass)
'bellow's last novel' is the wordplay.
'bellow' becomes 'cry'.
'novel' indicates anagramming the letters.
'last' with letters rearranged gives 'stal'.
'cry'+'stal'='CRYSTAL'
'is' acts as a link.
(Other definitions for crystal that I've seen before include "Clear quartz - fortune-teller's ball" , "Regular-shaped mineral piece" , "Quartz, for example" , "Globe for the fortune-teller" , "Highly-transparent glass" .)