Stones maybe using grand composer (6)
I believe the answer is:
gravel
'stones maybe' is the definition.
(gravel is made up of small stones)
'grand composer' is the wordplay.
'grand' becomes 'g' (G is short for grand as in a thousand).
'composer' becomes 'ravel' (Maurice Ravel).
'g'+'ravel'='GRAVEL'
'using' acts as a link.
(Other definitions for gravel that I've seen before include "Stone mixture for paths" , "Small stones on paths" , "Rocky fragments" , "bits of rock" , "Driveway surface" .)